To us, it was just “The Office.” But it was a mansion with a huge atrium, a pool, a waterfall, a koi pond, and a staff. We had women who cleaned, cooked, and did our laundry, and old men who maintained the grounds.

The Office was in one of Tijuana’s best neighborhoods, the equivalent of Beverly Hills, or Sutton Place in New York. Our neighbors were judges, politicians, businessmen, and old-money families that made their fortunes a hundred years ago in gold, oil, cattle, and crops.

Of course, everyone in the neighborhood knew exactly what was going on behind the walls of the Office. They couldn’t help but see the heavily armed 24-hour security force that patrolled the grounds or the caravans of SUVs, packed with armed men, coming and going in broad daylight. But the neighbors kept their mouths shut because we didn’t have any dealings with them. Our business was dope and murder, and our enemies were people whose business was dope and murder.

Occasionally the two worlds did collide, and we had to handle these “legitimate” people who decided to play with fire. Some of the kids in these wealthy families were fascinated by the life of a narco-terrorist and did business with us. Some did well. Others ended up melting in a barrel of acid.

The life of a millionaire was something I never thought I’d experience growing up as a street kid in San Diego. When I raised my hand to join the Tijuana cartel as a sicario, or assassin, I didn’t care that the price for living like a king was killing people. The people the cartel targeted were no better or worse than we were. They were just adversaries. Everybody on both sides knew that competition in the drug trade basically comes down to how many people on the other side we can kill before they give up. And that was our goal. Kill as many of them as we can until the attrition just wears them down.

Of course, they were trying to do the same to us.

A month after I’d left Calipatria State Prison in California and crossed the border into Mexico to work for the Tijuana cartel, I got my first assignment.

The cartel’s main assassin, David Barron, had killed close to a hundred people for the Arellano Félix Organization, or AFO. He used pistols, shotguns, rifles, machetes, knives, sledgehammers, chainsaws, and plain old meat cleavers. He liked to think of himself as a specialist, a methodical killer with a deep knowledge of the human body. Later, on some of our missions, he’d show me how and where to plunge the knife into a bound man who was screaming for his life.

David pulled me aside one morning and told me that the cartel’s leader, Ramón Arellano Félix, had ordered two assassinations. All I was told was that the targets lived in Los Angeles and they’d been part of the team that tried to kill Ramón at a discotheque in Puerto Vallarta the year before.

“El Chapo” Guzmán had sent 40 assassins into the club to kill Ramón and his brother Benjamin. Hundreds and hundreds of rounds were fired during the gunfight between Ramón’s people and Guzmán’s assassins. That night eight of Ramón’s bodyguards were killed, as were 10 of Guzmán’s men and something like a dozen innocent civilians.

It was a bloody massacre that should have made headlines all over the world. Or at the very least in the United States, the biggest consumer of the drugs we moved. The fact that it didn’t just indicates that American society is deluded in thinking that personal drug use is a victimless crime. Every ounce of pot or eight ball of cocaine or bindle of heroin that changes hands on the streets or in an executive suite or at an Oscar afterparty has blood on it. A lot of it is innocent blood. A lot of it isn’t.

The assassination attempt failed to kill Ramón, but he wasn’t about to let Chapo’s guys live to brag about it. He needed to send a message to Chapo that even his people living in the U.S. would not be safe from the long arm of Ramón’s retribution. The shooters had to die. And I was the one tasked with killing them.

This was going to be my first hit. And it was critical that it be done right. No fuckups. No arrows pointing back to Ramón. No footprints that could implicate the cartel. It had to be clean and fast. And I was going to be in charge.

One of the targets, a fat, slow-moving guy who was one of the shooters at the disco, was living large in L.A. dealing drugs for Chapo and probably feeling safe from any retaliation. Everybody knows that the cartels don’t commit murders in the U.S. It was to our advantage that people kept believing that. The reality is, more killings in the U.S. are committed on orders that originate in Mexico than anyone lets on. No one wants to talk about how little control they have over who comes in or what they do when they get there.

Chapo and the Arellanos had been at war for over a decade, since 1989, and nobody had any clear idea of the body count, but it was probably in the thousands.

David gave me $15,000 in getaway cash in case something went wrong. If I needed to buy a car, bribe a hotel clerk, or buy a gun on the street, I’d have enough for me and my crew to make it back to Tijuana.

Apart from worrying about actually killing one or more of my boss’s enemies, I was also stressing about going back to the U.S. I was a parole violator. I never checked in with my parole officer after I left prison. Could I make it across the border to San Diego without a nosy border agent running me through the NCIC? Would some L.A. gang cop size me up at a gas station and see what was up?

There was no way we could bring our weapons across the border. So David gave me the names of two Border Brothers gang members who lived in L.A. They’d set us up with guns, identify the fat dealer, and show us where he lived.

The cartels would not be able to ship a billion dollars of dope into the U.S. every year without a huge network on U.S. soil. It could be anybody. A middle-aged mother handling money and phone calls for the cartel in Palmdale. A construction worker standing outside a Home Depot in L.A. A couple of teenagers slinging dope in Compton. A civilian employee of the LAPD. Someone on staff in a city council member’s office. A Border Patrol agent.

David told me to pick two guys to go with me. There was no question. I picked the only two of my San Diego homeboys I could halfway trust to shoot straight and follow orders. They were both proven quantities, and they were both 17. Roach was an awesome driver who didn’t lose his shit in a gunfight or a police pursuit. Puma was a solid soldier with a lot of heart.

When you’re working for the dark side, you’ve got nobody to rely on except the guys standing next to you. Going deep into enemy territory is nothing like gangbanging or hitting a neighborhood enemigo from across the boulevard.

I wasn’t a gangbanger anymore. I was now the sharp tip of the spear of an international criminal organization. And at that level, you’re expected to perform like a professional. Excuses only make you dead.

So at 3:30 pm the next day, Puma, Roach, and I were waiting in line at the San Diego County border crossing. Puma was driving a red Toyota pickup. Roach and I were in a brand-new white Jetta. Both had plates legally registered to owners in California. That’s what a billion-dollar organization can buy you — an enormous support system of safe houses, documents, routes of entry and exit, intelligence networks and all the guns and people required to keep the organization running smoothly.

The Border Patrol guys saw the plates and barely gave us a second look when we flashed our California IDs. The border is so loosely enforced that the cartels can move anything they want through it. I was in the U.S. law enforcement computer system as a parole jumper. A few keystrokes on a computer would have shown that.

By 6 we were in Los Angeles. We checked in at a Ramada Inn and called the Border Brothers at the phone number that David had given me.

An hour later Chino and Chuy showed up at the room with our weapons: a fully automatic Uzi submachine gun equipped with a huge silencer, an M1 carbine, a .357 revolver, and a couple of 9mm semiautomatic pistols.

We’d use the Uzi for the initial engagement and then back that up with the heavier caliber. Basically, the Uzi sprays a lot of lead real fast, but it’s not that accurate. The idea is to hose off the opposition and get at least enough holes in them to get them down. Then we’d finish them off with head shots at close range with the .357 Magnum or the .30-caliber carbine. Believe it or not, it’s hard to kill somebody with a single shot in a gunfight. The only absolute, instant-kill shot is to the head. And you need to be close, and the target has to be still to get that shot.

I gave Puma and Roach $100 to get some food, and I started to plan the mission based on the information the Border Brothers had given us about our targets.

A few hours later, Roach and Puma came back with a couple of girls they met, and they basically partied and screwed until 3 in the morning, when the girls left.

Roach and Puma were young. And, although they didn’t say it, they were probably thinking that this could be their last night on Earth, so why the hell not get loaded and laid. I was 30 at the time. I had already reconciled myself to the fact that I wasn’t going to live much longer. Getting drunk and laid wouldn’t make me feel any better. Besides, getting loaded is a hazard. It makes you stupid and tired the next day. If I was going to survive, I needed to stay sharp.

Maybe the best I could hope for was a cartel funeral with a big headstone and a statue of Santa Muerte planted in the dirt over my body. I didn’t care. I had nothing holding me to the world of the living. I’d cut myself off from my parents and my siblings. I didn’t have a relationship with my wife or children. I was a fugitive from the California justice system. I didn’t have a single thing to look forward to or live for. In a way, I was already dead.

I assigned Puma the M1 carbine. Chuy, who wanted to be part of the team, got the .357 revolver, and Roach got one of the 9mm semiautomatics. I was supposed to have the Uzi, but whoever they got it from had drilled holes in the silencer, making it useless.

I called David and told him that I needed another weapon. A few hours later, a fully automatic TEC-22 showed up at the Ramada. It had two 40-round magazines loaded with hollow-point .22-caliber bullets that had been dipped in mercury. If the bullets didn’t kill the target right away, the mercury would eventually poison him. These rounds were reserved for the fat dealer, the guy we knew for sure was one of the shooters at the discotheque. He was the must-kill target. If we got anybody else connected to him, that was a bonus.

Once we had our weapons figured out, we started the surveillance. The street where we’d do the hit was in East L.A., not too far from the post office in the LAPD’s Hollenbeck Division. That part of L.A. has been a spawning ground for street gangs and Mexican Mafia shot-callers since before World War II.

We parked where the dealers wouldn’t see us and watched them. Roach and Puma were in the Toyota. Chuy and I were in the Jetta. We had Tijuana police radios, and we were using those to talk to each other. It turned out that three of Chapo’s people had rented houses and apartments on both sides of the street. And the way they worked is that they’d hang around in the front yard looking to the casual observer like just a couple of guys relaxing. But we could see that every few minutes, a car would pull up to the house and wait. One of the dealers would approach the car and serve the drugs.

Then the car would pull off, and the guy would go back to sitting in his yard. It was a drive-up franchise for dope — a Burger King for coke, meth, and pot. And this was just one of hundreds, if not thousands, of Chapo Guzmán’s retail dope outlets all over California and the rest of the country.

“That’s him. That’s the cabrón [dumb-ass],” Chuy said when the fat dealer first showed himself. I told my guys to memorize his face. He was the guy we needed to kill.

He was working with two other guys. I decided right there to hit all of them. I wanted to go back to the Office with a high body count. We watched them dealing most of the day. They were busy.

Once we’d memorized the guys’ faces, their houses, and how they worked, I started looking for ways to get in and out of the street fast. I sent our two Border Brothers away and drove all around the neighborhood with my shooters. We analyzed entry and escape routes. We went through a lot of what-if scenarios. What if they spot us early and run? What if they have shooters in the houses? Dope houses are prime targets for home invasions from rival gangs, so a smart dealer will post a security team behind the entrance with large-caliber weapons. So there was that to think about.

And then there was the issue of what would happen if the cops showed up. The Hollenbeck police station is only a few blocks away. They could get to us in half a minute once the bullets start flying.

We decided on where to meet up in case something went wrong and we had to scatter. The military calls this a rally point. We had two of them in case everything went sideways at the first rally point and we needed that secondary fallback position.

Then we started getting deeper into the mechanics of the kill.

You need to do all this groundwork if you’re in any way serious about committing an assassination and getting away with it. Little gangbangers and hotheads get caught because the only thing they’re thinking about is pulling the trigger. An assassin who’s worthy of the title knows that pulling the trigger is only about 10 percent of the job. The real work is the setup, planning for the “Oh, shit” moment when the plan falls apart, getting in, and getting away with it.

Once we had our scenarios down, I took the crew to a swap meet for our clothes.

We were operating in what the media likes to call a “gang infested” neighborhood, and from the second you enter a gang neighborhood, you’re being watched. What does your hair say about you? What about those tattoos? We can look at a tattoo and make an accurate guess as to what neighborhood you’re from, your status in the gang, if you’re a shot-caller or a soldier.

I picked out clothes that would send the message that we were not gang affiliated — hoodies in weird colors like brown, yellow, black, and green. To a gangster, those colors mean nothing. Casuals. The only color that counts is blue, the color of the Mexican Mafia–affiliated gangs in all of California. Don’t get caught wearing a blue jersey or a blue L.A. Dodgers ball cap. It could get you killed.

Then we got sweatpants and shorts to wear under them. The idea was that right after we did the hit, we’d strip off the jackets and sweatpants and dump them. After the shooting, the radio call would go out looking for three Hispanics in hoodies and sweatpants. By the time the units got that information, we’d be in T-shirts and shorts looking like every other Hispanic on the street.

Then I got everyone bandannas and gloves. We couldn’t dump the guns with our prints all over them, and we didn’t want GSR — gunshot residue — on our hands in case we were stopped and they got curious enough to give us a GSR test. So we found gloves that were thin enough to work a slide, press the mag-release button, and anything else we needed to do to keep a gun working in the middle of a firefight, but thick enough not to leave GSR on our skin.

We were committed to not getting stopped by the cops. We didn’t want to kill them. We thought, they’re just working guys like us. But they belonged to a government that wasn’t our government. And if it came to it, it was their tough luck that they couldn’t shoot first. We could.

After we did the hit and got back in the car, we would lock and load with topped-up magazines for battle. If we did get cops on our tail, we wanted to be ready to light them up. If a cop car got behind us, we’d be cool. But if the lights came on, that was our signal to bail out, fire everything we had at their windshield, and take off on foot.

We had one more day of surveillance and planning ahead of us. We showed up early in the morning and set up our monitoring of the dealers one more time.

It was like a dress rehearsal. We had everything we needed. We had the plan. We were spooled up and ready. All we needed was the opportunity to get these three guys out in the street at the same time.

And then. There it was.

We hadn’t planned on doing it that day or that moment, but it looked like Jesús Malverde, the patron saint of sicarios, had heard the assassin’s prayer and gave us the perfect opportunity.

All three of our targets were out in the street serving cars that had just pulled up. It was right around 9 on a Monday morning, and business was great.

I didn’t have to say much to the crew other than, “We’re doing it now.”

Roach drove the car and parked within a foot of where we agreed to park it. We tied off the bandannas, pulled up our hoodies, grabbed our guns, and started walking up the block.

I don’t know what it’s like being in an organized war in an army. But when I stepped out of the car with a full-auto weapon in hand, dressed in my battle gear, and focused on my enemy, I felt an enormous calm. Everything seemed to slow down, and I got a sort of tunnel vision. At the same time, I became aware of everything around me in sharp detail.

They were busy selling, so we got to about 10 feet of them before one yells out, “Agua! Agua!” That’s the distress call. What he saw was three guys in hoodies and bandannas walking toward him with their weapons raised and fingers on the triggers.

The first guy, the one closest to me, looked me in the eye and froze for less than a second. It’s all it took.

I already had the muzzle of the TEC-22 centered on his chest. I pulled the trigger and four mercury-tipped bullets hit him center mass. He was dead before he hit the ground.

The second dealer took off on foot, and Chuy followed him down a side street.

Puma, as he was ordered to do, immediately straddled the guy I had just shot and was about to put one in his brain, but I yelled at him not to bother, to go help Chuy find the runner.

All this took a handful of seconds that felt like forever.

The fat dealer was on the passenger side of his customer’s car. The car was between me and the fat guy, and I couldn’t get a shot at him with the driver there. I yelled at the driver to get the hell out of there. But the guy froze up. He wouldn’t move.

So I fired two rounds into his car, and he pulled away. Slowly. By the time he was clear, the dealer was about 20 feet away and running toward his front door.

I took my time, aimed, and squeezed, eight rounds blasting out of the barrel like water from a garden hose. The dealer rolled onto the ground. It looked like his legs just got chopped out from under him. But I could see he was still moving and crawling to his front door. I walked up to him, and I could see that I’d only hit him in the ass and the legs. The fat dealer rolled onto his back and said, “Non me mata. Por favor. Non me mata.” Don’t kill me. Please. Don’t kill me.

It was way too late for mercy. This guy was a sicario. Just like me. He was one of the 40 people who walked into a discotheque and sprayed lead all over the place, not caring how many people he killed. If the situation were reversed, he wouldn’t hesitate to kill me. I didn’t hesitate, either. It’s an ugly business. But it is a business.

I said to him, “Sí, puto. Por Ramón.”

I leaned over him and emptied the rest of the 40-round magazine into his body.

I looked up and down the street, and it was completely empty. This was a Monday morning around the time people were on their way to work or school, and there wasn’t a single person in sight. We’d just committed what we believed to be a triple homicide on a street in one of the biggest cities in the country, and I was the only living thing visible on the landscape.

Where were my guys?

I started for the car. Roach was already behind the wheel, and he and Puma were stripping off their bandannas and hoodies. But where was Chuy? I told Roach to wait and give me a few seconds.

I jumped out of the car with my weapon still in hand and ran up the street. There was Chuy, bent over at the waist, his gun still in his hand and both his hands on his knees. He was gasping for air. He’d chased the guy for a long time and finally hit him.

Chuy saw me. He smiled. He thought we left him behind. Then he told me he hit his man.

Time to go.

We ran back to the car, jumped in, and took off the bandannas.

I told Roach to drive slow. Don’t make it look like we’re escaping the scene. And the good soldier that he was, he drove down the street right past the bodies as cool and slow as Joe Citizen.

Our first turn out of there was onto Whittier Boulevard, three blocks away. If we could make it to Whittier, we’d blend in with the traffic and we’d be gone, back in Mexico by lunchtime.

But then we had to stop for a traffic light. And, as things like this happen, a black-and-white cruiser stopped behind us.

“Be cool,” I told the guys in the car. I also told them to check their weapons and make sure they were loaded with fresh mags.

It was a female cop driving without a partner. My stomach tightened because she might be a mother or a wife or both, and the thought of killing a woman, even if she was a cop, made me sick. But not sick enough to give her a pass.

I reminded my guys again. “If she puts her light on, we bail out. We light her up with everything we got and meet up at the first rally point.”

We sat frozen waiting for the red light to change. And then: Her light goes on. We went on full alert. We had our hands on the door handles ready to swing out and kill her.

Then she cranked her wheel hard, making a high-speed U-turn behind us, and took off in the opposite direction. She must have just gotten the shots-fired call. She’d come about three seconds from being executed.

We looked at each other. This was some crazy shit.

We pulled over to strip off our clothes. We threw the weapons and the clothes into a plastic bag and handed it to the Border Brother who was waiting for us.

As he took the bag to dump it, we started hearing sirens coming our way. A lot of them. We pulled out into traffic and drove down Whittier Boulevard to get to the freeway. A couple of cop cars drove past us to respond to the scene of our crime. It was beautiful.

We were back across the border and at the Office that afternoon.

The next day David came in with a suitcase and told us that the killings had started a shitstorm in L.A. He gave us each $25,000 in cash. He didn’t ask for the $15,000 he’d given me as getaway money.

The body count turned out to be only two out of three. The first guy I shot died on the spot. The fat dealer took two days to die from the bullets and the mercury. The third guy, who Chuy shot, survived.

I was a hero to David and Ramón Arellano. I led a team on a successful assassination and not only got away with it, but kept the LAPD and the entire California justice system in the dark about those homicides for more than a decade. Those murders remained unsolved until I eventually became a prosecution witness and told them how and why they happened.

Getting it done right does not make me proud now, but it did then.

Adapted from Confessions of a Cartel Hit Man, by Martin Corona with Tony Rafael, to be published in July by Dutton, a division of Penguin Random House. Corona cooperated with the U.S. government in prosecuting the Tijuana cartel. He lives with his family in witness supervision.

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