PORTLAND, Maine — A Portland man who police say stabbed a homeless couple as they lay sleeping on a mattress under Interstate 295 in May has been indicted for the alleged crimes, as well as for tampering with a witness.

Scott Decker, 36, was indicted Friday, Aug. 9, by a Cumberland County grand jury.

He faces one count of Class A felony elevated aggravated assault, one count of Class B aggravated assault, and a Class C count of tampering with a witness or informant.

Police say just before 11:30 p.m. on May 1, a 29-year-old woman walked into a Congress Street restaurant and said she and her 44-year-old boyfriend had been stabbed by a knife. The woman suffered from internal bleeding due to a lacerated liver. Her boyfriend, who police said also suffered serious injuries, was found by a Uber driver that night near the duck pond in Deering Oaks Park. 

The woman said the couple forced her from her apartment but demanded she continue to pay rent, and then threatened to kill her after a $2,000 check she wrote bounced, according to court documents. 

Decker was also indicted for an additional charge of tampering with a witness or informant after allegedly contacting a woman who was with him the night of the alleged stabbings.

Decker has remained in custody since his arrest in lieu of $20,000 bail, his attorney, Mark Peltier said Monday.

Decker, who has an extensive criminal record, has previously served time in prison for charges including aggravated assault, aggravated criminal trespass, assault, domestic violence assault, terrorizing and violation of a protective order, records indicate.