A 28-year-old man who police say led a loosely organized carjacking ring has been charged with committing two murders and two shootings as part of a weeks-long crime rampage — and investigators are probing whether his group is connected to dozens of other crimes.

Jonathan Akubu of Drexel Hill was arrested Saturday in connection with the fatal carjacking of a 60-year-old man killed Feb. 6 in Northeast Philadelphia. He is also charged with killing another man, a 28-year-old car locksmith, less than a week later in the city’s Eastwick section.

Detectives used ballistics and cell phone records to connect Akubu to at least five incidents in the last two months. He was arrested at an apartment in Lansdowne, where police found a stolen handgun and an AK-47-style rifle.

Akubu is so far the only defendant charged in each case. Homicide Capt. Jason Smith said Tuesday that investigators believe his carjacking operation targeted Toyota SUVs and involved at least three other people in their teens or early 20s who are at large.

Detectives were reviewing as many as 40 cases for potential links, law enforcement sources said, and were also investigating the possibility that some of the stolen vehicles that have not been recovered were shipped overseas.

Officials declined to comment on that theory during a Tuesday morning news conference. But they cast the case as an important example of law enforcement working together to address the city’s gun violence crisis.

”To all those who seek to sow chaos in our city,” said Mayor Jim Kenney, “let today send a message that we simply cannot and will not tolerate these acts of violence.”

Akubu is being held without bail on a litany of charges including multiple counts of murder, aggravated assault, conspiracy, robbery, theft, and illegally possessing firearms. He did not have an attorney listed Tuesday.

Carjackings have risen sharply in the city, with 203 reported through the first seven weeks of the year, according to police statistics — that’s nearly seven times as many as were reported by the same date in 2020 and more than in all of 2017. Other cities, including New York and Chicago, have also seen carjackings soar.

Police have said they believe many incidents appear to be crimes of opportunity, with cars recovered shortly after they’re stolen and likely used in joyrides or other crimes. But in some instances, authorities have said, newer cars have been stolen and not recovered. And investigators were looking into potential connections between the thefts of a handful of Toyotas in Northeast Philadelphia in recent weeks.

Commissioner Danielle Outlaw said Tuesday that police have created a task force dedicated to investigating carjackings and are collaborating with state and federal authorities.

“I refuse to accept that what’s happening here is OK,” she said.

Smith said investigators, using ballistics, have connected Akubu to incidents dating to at least Dec. 27, when a 25-year-old was shot in the shoulder during a carjacking on Greenway Avenue in Southwest Philadelphia.

The man’s Toyota RAV4 and a handgun were stolen, and the gun was later found in Akubu’s apartment. It’s the same one used in both murders with which he is charged, police said. Akubu was charged with receiving stolen property in the Greenway Avenue case.

A week later, several men tried to take a Toyota Highlander from a man on the 8400 block of Lyons Place in Southwest Philadelphia. One of them shot the 42-year-old driver in the leg as he tried to flee. Akubu is charged with aggravated assault in connection with that incident.

» READ MORE: Carjackings in Philly are on a record pace. Officials aren’t sure why.

He faces similar charges stemming from an incident a week later. On Feb. 4 on the 7600 block of Elmwood Avenue in Eastwick, a 45-year-old woman parked her Toyota RAV4 and was approached by three men who tried to grab her bag. When a man inside a nearby home opened the door, police said, the perpetrators shot at him, then fled in the Toyota.

Two days later, 60-year-old George Briscella was fatally shot on the 2100 block of Afton Street in Rhawnhurst. Three men ambushed him and stole his 2022 Toyota RAV4 around 8 p.m., police said, shooting him in the stomach.

Briscella, a Marine Corps veteran and grandfather, was headed to his mother’s home to use her printer, police said. Attempts to reach relatives for comment Tuesday were unsuccessful.

Police found his vehicle in Southwest Philadelphia around 7:30 a.m. on Feb. 12. Less than 12 hours later, officers responding to a shooting on the 8100 block of Grovers Avenue found Aiah Gbessay dead with three gunshot wounds to the head. A witness told investigators the shooters fled in a white van.

Minutes later and three blocks away, officers found a white van engulfed in flames. Investigators later learned it belonged to Gbessay, Smith said, and they believe Akubu set it ablaze.

Police sources said that Akubu and Gbessay knew each other. Cell phone records suggest the two men were in contact minutes before the killing, according to court papers.

Gbessay’s older brother, Francis Sankoh, 32, said Gbessay ran his business as a car locksmith in Southwest Philadelphia, printing or programming keys. He said Gbessay was extremely conscientious and had gone to technical school to learn his craft.

Family members have been speculating about reasons he may have been killed, Sankoh said: perhaps an argument over a specific job. But he did not believe Gbessay was a part of the alleged carjacking operation.

”He’s not the kind of person to ever interact ...with that kind of activity,” Sankoh said.

Sankoh said his brother’s wife and 11-year-old son had recently moved to Philadelphia from their native Sierra Leone and are devastated by his killing.

”Nobody deserved what happened to my younger brother,” Sankoh said. “He has a son and now the son is going to grow up without a father.”

Akubu has several past arrests, records show, including in Chester County in 2020 for charges that included robbing a car. But nearly all counts were dismissed in municipal court, the records show. It was not immediately clear why. Akubu pleaded guilty to a summary charge of harassment, the records show.

Years before that, Akubu pleaded guilty to committing a 2013 aggravated assault in Southwest Philadelphia. According to charging documents, he fired shots at someone in a car using a gun he was barred from possessing. He was sentenced to 38 to 96 months in jail plus 17 years of probation, court records show, and in 2018 was sent back to jail for violating his probation.

In 2015, Akubu filed a federal lawsuit against the city, saying that a prison guard beat him and bit him on the head while he was handcuffed, an incident that was captured on surveillance video. The city settled with Akubu for $99,999, which was paid in November 2015.

Staff writer Jeremy Roebuck contributed to this article.