Fort Lauderdale, Florida (CNN) Two of the three charges against Fort Lauderdale airport shooting suspect Esteban Santiago carry the possibility of the death penalty, a federal magistrate judge told Santiago on Monday.

The charges handed down are using and carrying a firearm during and in relation to a crime of violence; performing an act of violence against a person at an airport serving international civil aviation that caused serious bodily injury; and causing the death of a person through the use of a firearm.

The latter two are punishable by death, while the first charge carries a maximum penalty of life in prison.

Authorities claim Santiago has confessed to the Friday mass shooting at Fort Lauderdale-Hollywood International Airport that left five people dead.

Santiago, 26, entered the court in a red prison jumpsuit and sat down. He kept his head down throughout his first court appearance. He told US Magistrate Judge Alicia O. Valle that he understood his rights before explaining he was not employed and had served in the Army for about 10 years.

He owns no car or property, he said, and has only $5 or $10 in his bank account.

Valle appointed Santiago a lawyer. His next court date is January 17, and his arraignment is slated for January 23.

Since the shooting, details about the attack, the victims and how the suspect may have "slipped through the cracks" have emerged. Here's what we know:

The suspect's background and travels

Suspect Esteban Santiago is being held in federal custody in Florida.

-- Santiago, a security guard living in Alaska, had served in the US Army Reserve and the Alaska Army National Guard. He completed a 10-month tour of Iraq from 2010 to 2011.

-- After his time in Iraq, his aunt and brother said, he came back a changed man -- hearing voices or having "visions all the time."

-- Santiago recently began selling his possessions, including his car. Friends and associates noticed more erratic behavior, investigators have learned from interviews with those who know him.

This composite photo shows views of the room where Esteban Santiago was living in Anchorage.

-- The suspect rented a small room at Qupqugiaq Inn, an Anchorage motel. The FBI searched the room on Friday night.

-- Two months ago, Santiago voluntarily went into the Anchorage FBI office and said his mind was being controlled by US intelligence. He was "having terroristic thoughts and believed he was influenced by ISIS," Anchorage police said.

-- At that time, authorities took away his gun and ordered a mental health evaluation. But he was not deemed mentally defective, so authorities later gave him back his gun . Sources say it was the same gun Santiago used in Friday's rampage.

JUST WATCHED Suspect's brother: 'He was a peaceful person' Replay More Videos ... MUST WATCH Suspect's brother: 'He was a peaceful person' 02:28

-- "We had this situation where he slipped through the cracks," CNN national security and law enforcement analyst Tom Fuentes said. But Karen Loeffler, the US Attorney for the District of Alaska, said she thinks "law enforcement acted within the laws that they have."

-- Santiago told investigators he bought a one-way ticket from Anchorage to Fort Lauderdale and brought a Walther 9-millimeter pistol and two magazines.

-- A lieutenant with the Anchorage airport police said Santiago had one checked bag -- a handgun case containing a pistol.

-- Though authorities do not yet know Santiago's motive, the FBI has not ruled out terrorism.

-- The day before the shooting, Santiago spoke to a sibling in Florida and told him he wanted to visit, but Santiago didn't say he planned to take a flight the next day, according to another sibling, Bryan Santiago, who lives in Puerto Rico. Bryan Santiago said he also didn't know his brother would be traveling to Florida on Friday.

Video of shooting released

JUST WATCHED When the gunman opened fire Replay More Videos ... MUST WATCH When the gunman opened fire 01:42

Security footage obtained by TMZ shows the seconds before and after the shooting. The gunman walks through the baggage claim area at Fort Lauderdale-Hollywood International Airport, just steps behind a man and two boys, and pulls a handgun from his waistband.

The gunman then fires about three times before running out of the camera's view. A couple sitting nearby drops to the ground. A woman ducks behind a baggage cart. Several people, seeing nowhere to take cover, dive face-first to the ground.

After the deadly rampage, Santiago was arrested without incident, authorities said.

Photos: Fort Lauderdale airport shooting People run out on the tarmac in the aftermath of the shooting Friday, January 6, at the airport in Fort Lauderdale, Florida. Five people were killed and eight others were wounded , officials said. Hide Caption 1 of 12 Photos: Fort Lauderdale airport shooting People stand on the tarmac at Fort Lauderdale-Hollywood International Airport after a gunman opened fire inside Terminal 2 on Friday, January 6. Hide Caption 2 of 12 Photos: Fort Lauderdale airport shooting People take cover outside the airport in the chaos following the shooting. Hide Caption 3 of 12 Photos: Fort Lauderdale airport shooting Law enforcement personnel arrive in an armored car outside the airport. Hide Caption 4 of 12 Photos: Fort Lauderdale airport shooting Law enforcement personnel stand outside a garage area at the Fort Lauderdale-Hollywood International Airport. Hide Caption 5 of 12 Photos: Fort Lauderdale airport shooting Police assist people seeking cover outside Terminal 2 at the Fort Lauderdale airport. Hide Caption 6 of 12 Photos: Fort Lauderdale airport shooting People react after the shooting at the Fort Lauderdale airport. The first call about the incident came in at 12:55 p.m. ET, authorities said. Hide Caption 7 of 12 Photos: Fort Lauderdale airport shooting Officials said it's too early in the investigation to know for certain what prompted a man to open fire on people at the baggage claim area in Terminal 2. Hide Caption 8 of 12 Photos: Fort Lauderdale airport shooting Law enforcement officers arrive at the Fort Lauderdale-Hollywood International Airport. Hide Caption 9 of 12 Photos: Fort Lauderdale airport shooting A shooting victim is taken into Broward Health trauma center in Fort Lauderdale. Eight people were being treated there after they were injured at the airport, officials said. Hide Caption 10 of 12 Photos: Fort Lauderdale airport shooting Police officers stand on the perimeter road at the Fort Lauderdale-Hollywood International Airport. Hide Caption 11 of 12 Photos: Fort Lauderdale airport shooting A ground stop was issued for the Fort Lauderdale airport after the shooting. Most flights scheduled to land will be delayed or diverted, and no flights will depart for the time being, the FAA said. Hide Caption 12 of 12

The victims

Terry Andres was at the airport with his wife, about to start a vacation ahead of his 63rd birthday. His wife was not wounded.

"He and Ann were married for 40 years, and he absolutely adored his children and grandchildren," said a longtime friend who wanted to stay anonymous.

In the case of Michael Oehme's death, there were public condolences from state Sen. Chuck Grassley of Iowa.

"Pray as I will for Oehme family of CouncilBluffs Iowa /Father Michael was killed and Kari the mother was wounded at FtLauderdale Massacre," Grassley tweeted.

Pray as I will for Oehme family of CouncilBluffs Iowa /Father Michael was killed and Kari the mother was wounded at FtLauderdale Massacre — ChuckGrassley (@ChuckGrassley) January 8, 2017

Shirley Timmons, 70, had been married for 51 years to her high school sweetheart, and "together they built a close, loving family with their three daughters, three son-in-laws and eight grandchildren," her grandson Steve Reineccius said in a statement. "For Shirley, family meant vacations, football games and holiday traditions."

Olga Woltering, 84, and her husband, Ralph headed to Fort Lauderdale for a cruise. Her husband was not seriously wounded.

"Olga was one of the most joyful, loving, caring and committed people I have ever met," the Rev. Fernando Molina-Restrepo of the Catholic Church of the Transfiguration in Marietta, Georgia, said.

Two of the injured victims remained in intensive care late Sunday, while the remaining four had been released or were recovering at Broward General Hospital, Sheriff Scott Israel said.

The hospital gave slightly different numbers, saying seven victims -- including five who had been shot -- remained hospitalized Sunday. One gunshot victim was released Saturday, the hospital said.