(CNN) It's not uncommon for Filipinos to have nicknames: sometimes holdovers from childhood; sometimes affectionately acquired as young adults.

Philippine National Police (PNP) Chief Ronald Dela Rosa's moniker -- "Bato," which translates to "the Rock," is one of the more apt -- an immovable, unbreakable object.

Dela Rosa has shot to fame thanks to his close relationship with the country's new strongman leader Rodrigo Duterte. He's also made a name for himself as the man behind the President's controversial war on drugs, which has seen hundreds of alleged dealers killed in a matter of weeks.

Ronald Dela Rosa was appointed head of the Philippines' national police in June.

Dela Rosa got his nickname back in the early days of his career, just after graduating from the Philippine Military Academy. After completing his ranger training he was transferred to his hometown of Davao.

"When I was (first) seen by my senior officers, my body was like a rock... rock solid. So they told me, 'Bato!' They start calling me 'Bato' because of my build.

With his gleaming bald head and barrel chest, the well-built former military man even resembles one.

"Later on they realized that I was born and raised in Barangay Bato, Santa Cruz, Davao Del Sur -- that's my birthplace, Barangay Bato."

"So that was reinforced until now. They keep calling me 'Bato.' I cannot change it anymore," he laughs.

JUST WATCHED Philippines cracks down on drugs Replay More Videos ... MUST WATCH Philippines cracks down on drugs 02:27

From Barangay Bato to police HQ

It's been a long journey from that childhood neighborhood to the highest echelon of law enforcement in the country, and it's one that he's taken, in part, with Duterte.

Bato was his police chief when the pair were in Davao, prior to their swift rise to national prominence.

He says he doesn't like life in Manila -- "Davao is very disciplined; we have a low crime rate."

He's enjoyed a stratospheric rise, from a one-star general as chief of police in Davao to the national top job in one fell swoop.

Critics say that he's only achieved his position thanks to his long association with Duterte, but he counters naysayers, arguing it's within the President's remit to choose any general for the role.

Photos: Philippines drug crackdown Police patrol a shanty community at night during curfew on June 8, 2016 in Manila. Hide Caption 1 of 9 Photos: Philippines drug crackdown Some 1,000 people whom authorities accused of being drug users and dealers take an oath before local authorities after turning themselves in in Tanauan, the Philippines, on July 18, 2016. Hide Caption 2 of 9 Photos: Philippines drug crackdown A man authorities accused of being a drug user is fingerprinted during the mass surrender of some 1,000 alleged drug users and pushers in the Philippine town of Tanauan, located about 37 miles (60 kilometers) south of Manila on July 18, 2016. Hide Caption 3 of 9 Photos: Philippines drug crackdown A social worker gives counseling to those who have turned themselves in for drug-related crimes in the Philippines on July 18, 2016. Hide Caption 4 of 9 Photos: Philippines drug crackdown A woman cradles her husband, next to a placard which reads "I'm a pusher," who was shot dead in Manila on July 23, 2016. Hide Caption 5 of 9 Photos: Philippines drug crackdown A Philippine police forensic investigator displays packets of drugs and a hand gun found inside a shanty where members of a suspected drug syndicate were killed after a shootout with police on July 3, 2016. Hide Caption 6 of 9 Photos: Philippines drug crackdown A suspected female member of a drug syndicate is presented by police in Manila on June 22, 2016. Hide Caption 7 of 9 Photos: Philippines drug crackdown A gun, bullets, marked money and sachets of crystal meth are laid on a table after a drug raid in Manila on June 20, 2016. Hide Caption 8 of 9 Photos: Philippines drug crackdown Police officers stand in formation before the start of "Oplan Rody" on June 1, 2016, a law enforcement operation named after President Duterte, whose nickname is Rody. Hide Caption 9 of 9

'Long time association'

He's known Duterte for three decades, he says.

He remains remarkably close to the tough-talking leader, and jokes to CNN that he has a telepathic connection with the man they call "the Punisher."

"We trust each other, in a very long time association. He knows what I'm capable of doing and I know what he wants to be done.

"So without saying any word we can communicate with each other, through mental telepathy," he says, mimicking their thoughts passing through the ether, before bursting into laughter.

"He's the best leader in the universe for me. He's a no-nonsense leader."

Hardline crackdown

Tasked with transforming the Philippines, one of the poorest countries in Asia into a "drugless society," he's approached the task with an admirable zeal, if somewhat questionable methods.

JUST WATCHED War on Drugs: Quezon City patrol Replay More Videos ... MUST WATCH War on Drugs: Quezon City patrol 01:31

He's expanded his "tokhan," or "knock and plead" operations, from a local experiment to national -- if unofficial -- police policy.

The operations, his "brainchild," see heavy-handed groups of police tour local neighborhoods and politely ask suspected drug users to voluntarily surrender.

The tactic has seen over 700,000 such surrenders in two months. But when confronted with a phalanx of heavily armed officers, it is hard to see who would refuse to comply.

Photos: 'Knock and plead': Persuading Quezon City drug users to register A Quezon City SWAT officer holds a shotgun during a "knock and plead" operation, as part of President Rodrigo Duterte's war on drugs. Police officers knock on doors to ask drug users to voluntarily surrender. Hide Caption 1 of 8 Photos: 'Knock and plead': Persuading Quezon City drug users to register An armed officer accompanies a "knock and plead" operation in the Bangaray Labis slum in Quezon City. Hide Caption 2 of 8 Photos: 'Knock and plead': Persuading Quezon City drug users to register Officers and the neighborhood "captain" Leny Glivano talk to a resident during a late night visit. Hide Caption 3 of 8 Photos: 'Knock and plead': Persuading Quezon City drug users to register The "knock and plead" operations involve going to the homes of those suspected of using methamphetamine -- and inviting those inside to accompany the police to the local town hall. Hide Caption 4 of 8 Photos: 'Knock and plead': Persuading Quezon City drug users to register At the hall, those rounded up sit around a starkly lit room, waiting to be registered as drug users. They are interviewed by police about local dealers. Hide Caption 5 of 8 Photos: 'Knock and plead': Persuading Quezon City drug users to register Hands raised, the detainees recite a pledge that affirms that their surrender is voluntary. They promise to "undertake to stop all" drug-related activities. Hide Caption 6 of 8 Photos: 'Knock and plead': Persuading Quezon City drug users to register Mug shots are taken, and those surrendering are required to provide a urine sample for drug testing. Hide Caption 7 of 8 Photos: 'Knock and plead': Persuading Quezon City drug users to register The detainees are also fingerprinted -- but the Philippines National Police Chief, Ronald Dela Rosa, tells CNN that the surrenders are not arrests. Hide Caption 8 of 8

War on drugs: No national strategy

The President instructed him to replicate his successes from Davao across the country, but so far he hasn't issued any written guidelines for how local forces should proceed.

"We don't need" a national strategy, he says. "We've been doing this for a long time."

In the two months since Duterte's war on drugs began, his officers had arrested 10,153 drug pushers and users, he said in testimony to a senate inquiry in late August.

In 6,000 police operations, he said drugs worth 2.38 billion pesos ($51 million) had been seized. CNN could not independently verify the figures the government provided.

But the impressive numbers have come at a very visible human cost.

There have been 756 suspects killed in police operations since the war on drugs began, alongside 1,160 drug-related killings that have occurred, many of which have been attributed to vigilantes.

'I hate extrajudicial killings'

In one breath he says he "hates extrajudical killings," but in the next he says there are benefits to the spate of deaths. He admits to "mixed emotions," when he sees images of suspected drug dealers gunned down.

"I pity the guy for losing his life but at the same time I see that there is one less pusher."

But what would he say to family members who have been killed? "Please do not be afraid of police. I guarantee we will protect you."

He's given himself six months to prove his mettle -- "If I fail, I will surrender. I will tell (Duterte) to please relieve me from my post. (I'll tell him) I cannot win this war."

Is ridding a country such as the Philippines of drugs in just six months a realistic goal?

"No. But if you aim high you can achieve acceptable levels."

Human rights concerns

There are concerns among human rights activists that the death squads that used to stalk Davao City have also been exported countrywide.

But Bato says he's ordered his officers to investigate and make arrests. But he denies that he tolerated the gangs while police chief in his hometown.

"Maybe. Maybe a coincidence. But please don't accuse me. I'm not the one bringing these death squads here in the Philippines," he says.

"I have been challenging this death squads in Davao City to come and get me. Instead of killing these helpless people... they can face me in a gun duel. I am challenging these vigilantes. You can fight it out with me if you want to kill somebody."

He points to the president's sky-high approval ratings as proof that the country is desperate for tough measures.

"A lot of support. A lot of support. This is borne out of frustration," he says.

"The past situation where drugs were being sold on the street like candies and innocent people are being killed, being raped by these drug crazed people, by the drug addicts... we are delivering his promise."

But is it worth the bodies piling up in the trash-strewn streets of poor neighborhoods across the country? These aren't desperate measures, he says. "We just have to do our job."