UTAH STATE PRISON — Two Utah prison inmates who practice Islam say state corrections officials are unlawfully keeping them from weekly congregational prayers.

Christopher Tolton and Davey Joe Williams have filed a federal lawsuit to be able to freely exercise their religion and participate in Jumu’ah, an obligatory Friday noon prayer.

“A person who misses Jumu’ah, even for a valid reason, cannot make it up,” Tyler Hawkins, a lawyer for the two men wrote. “Plaintiffs sincerely believe they must regularly participate to be eligible to reach heaven.”

Tolton, 44, and Williams, 42, are faithful, devout practitioners of Islam, of which prayer is one of the pillars and the most important of all Islamic duties, according to the lawsuit.

Tolton is serving a life sentence for the 1997 murder of a 21-year-old man during a drug buy. Williams served time for being an accomplice in the killing before being paroled. He’s now in prison for aggravated assault in a 2011 case involving his girlfriend.

Both men are incarcerated at the Central Utah Correctional Facility in Gunnison

The corrections department does not comment on pending litigation, said Kaitlin Felsted, prison spokeswoman.

“However, our staff works hard to accommodate the religious exercise of all inmates while also maintaining the safety and security of the department’s correctional facilities,” she said.

Prison officials have denied the two men regular Friday prayers for several years, the lawsuit says.

Members of religious groups are allowed to meet for weekly or more frequent prayer or other services as well as gather for purposes such as attending classes taught by other inmates, according to the lawsuit.

Tolton and Williams used the prison grievance process to request regular Jumu’ah but have been refused, the lawsuit says. The suit claims the prison is violating the Religious Land Use and Institutionalized Persons Act.

The lawsuit seeks an injunction ordering the prison to permit to the two men to congregate for the purpose of prayer and religious study.

In May 1997, Tolton and Williams got into the back seat of a car with Arthur Sanchez, 21, and Carlos Chavez, who was 15 at the time. Prosecutors said the group was originally planning a drug deal. Instead, Tolton shot and killed Sanchez from point blank range in the face.

Williams was paroled from after serving a little under 11 years for his convictions on kidnapping and robbery charges. A second-degree felony murder charge was dismissed as part of a plea deal.

While on parole in 2011, Williams threatened his girlfriend and her sister with a knife and gun in a West Valley apartment. He pleaded guilty to two counts of aggravated assault and possession of a dangerous weapon by a restricted person. A judge sentenced him to up to 15 years in prison and consecutive to his previous convictions.