COLUMBIA , Ill. — The task force investigating the Coleman family murder disbanded Friday, with its detectives saying they identified the killer to the prosecutor and the rest is up to him.

Monroe County State's Attorney Kris Reitz has deferred a decision on charges while awaiting results of unspecified forensic tests.

Police have not publicly disclosed their suspect in last week's killings of Sheri Coleman, 31, and sons Garett, 11, and Gavin 9, in their bedrooms at home in Columbia, Ill.

They did say they believe it was someone who acted alone and targeted the victims for murder.

The only surviving member of the household is Christopher E. Coleman, who told police he was working out at a gym in St. Louis County when his wife and children were killed, sometime between 5:45 and 7 a.m. May 5. Neighbors said police told them the three were strangled.

Columbia police called in the Major Case Squad, a cooperative of departments that share manpower and expertise in the early stages of a big crime, usually for five days.

The commander in this case, Maj. Jeff Connor of Granite City police, said 20 detectives worked sometimes day and night for 11 days, and traveled as far as Florida and Chicago. He said that team's services remain available if needed but that Columbia police will lead the investigation from here.

"We appreciate the public's help and support during this critical investigation and we are still optimistic this crime will be solved," Connor said in an e-mail to reporters.

Coleman had complained of some kind of threats related to his work in security for the Joyce Meyer Ministries, in Jefferson County. He resigned Wednesday. The ministry released a statement Friday that said an internal inquiry showed he "failed to follow ministry policy during his employment."

It was not explained if that had any connection to what police sources have said was more than one romantic rendezvous Coleman had with a Florida woman, a friend of his wife's, during out-of-town ministry trips.

Neither Coleman nor his lawyers have commented on the report of an extramarital affair.

Friday's statement from Meyer's organization also said it is cooperating fully with authorities in the investigation.

Elizabethe Holland of the Post-Dispatch contributed to this report.