Relatives of a Salvadoran immigrant who died after being held at a troubled detention center in Newark gathered outside a church on Tuesday pleading for answers about the circumstances that led to the man’s death.

Edwin Lopez-Cornejo, 41, was taken from the Delaney Hall detention center to University Hospital in Newark, where he was pronounced dead on Saturday. His family members appeared before news cameras on Tuesday to demand that state officials investigate Mr. Lopez-Cornejo’s death. They also called for the closure of Delaney Hall and for the release of detainees held there.

Mr. Lopez-Cornejo’s mother, Maria Cornejo, said in a phone interview on Tuesday morning that she did not understand why he had died and said that federal immigration officials had refused to provide his medical records to the family. Mr. Lopez-Cornejo is survived by a 12-year-old daughter, his mother said.

“The pain that I feel is irreparable,” Ms. Cornejo said. “His daughter is devastated.”

Family members, who stood on the steps of the church, held Ms. Cornejo by the arms as she approached the news cameras and placed their hands on her shoulder while she spoke to reporters and cried. When she was finished, she hugged her granddaughter.

Ms. Cornejo said that her son had been diagnosed with diabetes and epilepsy but that the conditions were managed for years with medication. She said she did not know if detention officials had been giving him his medication since he was arrested while walking to work on June 18 near his home in Plainfield, N.J., where he had a job in construction.