A Salvadoran immigrant who was being held at a troubled federal detention center in Newark died during the weekend, federal officials confirmed Monday evening.

The man, identified by immigration officials as Edwin Lopez-Cornejo, was being held at the Delaney Hall detention center in Newark, which has faced scrutiny and protests over the treatment of detainees.

The Immigration and Customs Enforcement agency, which oversees Delaney Hall, said that Mr. Lopez-Cornejo, 41, was pronounced dead on Saturday by medical workers at University Hospital in Newark. After Mr. Lopez-Cornejo experienced a medical emergency at Delaney Hall, employees “responded immediately and called 911 for emergency medical services,” the agency said. The cause of his death was not known.

Mr. Lopez-Cornejo is the second Delaney Hall detainee to have died in the past eight months.

“In less than a year, yet another family is forced to endure the unimaginable loss of a loved one while in custody at Delaney Hall,” Ras Baraka, the mayor of Newark, said in a statement.