Scattered protests broke out in Haiti’s capital on Wednesday as gasoline shortages added to concerns over insecurity and police announced new arrests a week after the assassination of President Jovenel Moise pitched the already-troubled Caribbean nation into political chaos.

Nearly all the gas stations in Port-au-Prince were closed and long lines formed outside the few that were still operating, with residents blaming both the criminal gangs that control key supply routes and opportunistic black market fuel sellers paralyzing distribution into Haiti’s biggest city.

Some protesters set tires ablaze in the middle of gritty streets, which remained quieter than usual in the aftermath of Moise’s killing early on July 7.

Moise was shot dead at his home by what Haitian authorities describe as a unit of assassins, including 26 Colombians and two Haitian Americans.

Haiti President Jovenel Moise assassinated at his home:

Eighteen of the Colombians were detained, three were killed by police and five were still on the run, Haitian police said.

A third Haitian-American, Christian Emmanuel Sanon, was arrested on Sunday by Haitian authorities, who accused him of being a mastermind of the attack.

Haitian police announced Wednesday that they arrested two more men after searching their homes and finding weapons.

Police said at a news conference that 24 police officers have been subjected to “precautionary” measures and four were in isolation as part of the investigation.

National Police chief Leon Charles identified former Haitian Senator John Joel Joseph as a key player in the plot. He supplied weapons and planned meetings, Charles said, adding that police were searching for him.

Charles also pointed a finger at a company he identified as World Wide Capital Lending Group as being responsible for fundraising “to execute this criminal act.”

World Wide Capital Lending Group, which is based in Florida, did not immediately respond to a request for comment.

Colombian news outlet Semana reported that one of the Colombians in custody confessed on Wednesday afternoon to Haitian authorities that seven of the Colombian suspects were what it called the “killers” of Moise, without elaborating.

Semana did not provide a source for the apparent confession, which it said the retired soldier had made “in tears.”

The report was not verified by Reuters, and Colombian officials did not immediately respond to a request for comment.

Prosecutors have been preparing to question the head of Moise’s security team, Dimitri Herard. It was not clear if the questioning has yet taken place.