An inmate who died last week in the Cumberland County Jail had swallowed a drug-filled balloon before being taken into custody and it burst inside him, causing an overdose, his lawyers say they were told by jail officials.

Nikco Bashari Walton, 24, of Portland, died at the jail on April 11. He had been admitted on April 5.

Walton’s attorneys, Cory McKenna and Amy Fairfield, said Tuesday they are skeptical that Walton could have carried a drug-filled balloon in his intestines for a week. More likely, they say, is that Walton obtained the drugs that killed him after he was incarcerated.

Either scenario, they said, raises security concerns about the state’s busiest jail, which had taken steps to curb the amount of illegal drugs being smuggled in.

The jail administrator, Maj. John Costello of the Cumberland County Sheriff’s Office, did not return a phone call seeking information about Walton’s death and about the jail’s policies on inmate searches and scanning procedures for finding drugs being smuggled into the jail. Sheriff Kevin Joyce was unavailable for comment.

Walton’s mother, Nathelle Pulley, said she flew to Maine from her home in Michigan the day after her son’s death, hoping to get answers. But investigators told her little, she said.

“I don’t know what’s going on, and I don’t like it,” Pulley said over the phone from Michigan. “I need to know what happened to my son. I need to know.”

Pulley said she is preparing for her son’s funeral Saturday at their home in Holland, Michigan, unsure what she will tell the family and others close to him.

Mark Belserene, the administrator at the state Medical Examiner’s Office, said it will likely take another week or two until tests are completed and he can confirm what caused Walton’s death.

“Regardless of any speculation, we can’t release any information until the case is finalized,” Belserene said.

Although Walton was in the custody of the Cumberland County Sheriff’s Office when he died, the Portland Police Department is investigating, as it does all suspicious or unattended deaths in Portland.

Lt. James Sweatt, a police spokesman, said detectives have asked the sheriff’s department to review all jail video to determine whom Walton had contact with prior to his death.

“We’re waiting for the Medical Examiner’s Office to conclude their report, and we will review it,” Sweatt said.

FAMILY LEFT IN DARK

Walton had been held at the jail for nearly a week before he was found unresponsive around 6:40 a.m. on April 11. Medical workers were unable to revive him.

He was arrested in Gorham on April 5 on a cocaine possession charge and was being held for allegedly violating the terms of his probation on a heroin possession conviction from 2015. Walton had tested positive for cocaine in his system as recently as April 4 during a routine test at the Portland Probation Office.

Any cocaine in his system at the time of his arrest would have long been metabolized by the time he died.

McKenna represented Walton during a probation hearing at the Cumberland County Courthouse on April 8. At that time, McKenna said, Walton seemed clear-headed and healthy, showing no signs of drug use or withdrawal.

McKenna said he spoke to police after Walton’s death. They told him Walton’s cellmate said Walton had slept through the night before his death and that Walton had vomited in his sleep that morning.

McKenna said police told him they expect autopsy results to show that Walton had swallowed a drug-filled balloon that burst in his intestines instead of passing through intact. Sealing drugs in a balloon and swallowing it is a common method of smuggling drugs.

“It seems like they have a conclusion that they’ve drawn from mere speculation and are waiting for evidence to support it rather than finding the evidence first,” McKenna said. “They want a certain answer and they are looking at that through that lens.”

McKenna said investigators seem to have ruled out the possibility of Walton obtaining the drugs that killed him from someone at the jail.

Fairfield said Walton’s parents, Pulley and Lamarkco Walton, couldn’t get any information from the jail staff or investigators.

“Here the parents have been treated with complete and total disrespect. They’ve gotten no answers. They haven’t even been given the time of day, and they have a dead son,” Fairfield said.

The Portland jail is the busiest in the state, holding up to 500 prisoners at a time, with a constant flow of inmates coming in or being released.

About 65 percent of the inmates are held temporarily while awaiting court appearances after arrest or being held on bail pending trial. They typically face charges ranging from driving with a suspended license to murder.

The other 35 percent are serving short sentences. Those convicted of serious offenses are sentenced to state prisons.

JAIL LACKS FULL-BODY SCANNER

Costello said in a previous interview that jail staff usually catch most incoming inmates who are trying to smuggle drugs. He has pushed unsuccessfully to increase security by adding technology such as a full-body scanner similar to those owned by the state Department of Corrections. But the sheriff’s office can’t afford the scanner’s $205,000 price tag.

Last year, the jail staff had begun transporting inmates held because they can’t make bail to the Maine Correctional Center in Windham, which has a full-body scanner that can detect drugs hidden inside a person’s body, Joyce said at the time.

Through the scans and strip searches, jail staff are able to intercept most contraband drugs. But federal inmates held at the jail temporarily are not always subject to the same search techniques as state inmates, Joyce said.

It is unclear whether county jail staff are still using the scanning machine in Windham.

There were three reported inmate deaths at county jails in Maine last year. Two deaths have been reported so far this year, according to Jody Breton, the deputy commissioner of the state Department of Corrections.

There were five inmate deaths reported at state-run prisons in Maine last year. In 2016, there has been one.

The Maine Department of Corrections reviews the circumstances of all inmate deaths, but does not investigate the cause.

Staff Writer Dennis Hoey contributed to this report.