Updated

A southwestern Illinois man was charged Tuesday with strangling his wife and two young children.

Chris Coleman, 32, was arrested at his parents' home in Chester, about 40 miles from Columbia, and charged with three counts of first degree murder, said Jeff Connor of the Major Case Squad of Greater St. Louis.

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"We've done all we could to solve this as quickly as we could but as efficiently as we could," said Connor, who declined to discuss motive. "We feel very comfortable in these charges."

Coleman did not resist arrest, Connor said. Coleman, wearing an orange jail jumpsuit and with his arms shackled to his waist, refused to answer reporters' questions as police escorted him to a waiting vehicle.

Defense attorney William Margulis told The Associated Press his client planned to plead not guilty at a court appearance scheduled for Wednesday.

Police had said they believed one person was responsible in the killings of Sheri Coleman, 31, and her two sons, Garett, 11, and 9-year-old Gavin, who were found in their Columbia home on May 5.

Connor confirmed on Tuesday that all the victims were strangled with a ligature but he declined to discuss the type of cord used.

The Major Case Squad presented evidence in the case to Monroe County State's Attorney Kris Reitz last week, but Reitz did not file charges pending the results of forensic tests. At the time authorities declined to name the suspect.

"For several days now we have been close," Connor said. "Tonight there was just some more evidence that came forward and we were able to solidify a more solid case."

The case remained open, although authorities were not looking for any other suspects, said Columbia Police Chief Joe Edwards.

Edwards said he was relieved Coleman had been arrested.

"We knew there was a road we needed to go down, a goal we needed to reach," he said.

The day the bodies were found Chris Coleman called police from a gym and asked a Columbia police officer who had investigated prior threats related to the family for a well-being check around 7 a.m., investigators have said.

Chris Coleman told officials that he called the house and no one answered, authorities said.

Officials have declined to discuss details about the alleged threats. Some neighbors in the well-kept subdivision have also said the Colemans received threatening letters and that their mailbox was tampered with.

Police got to the suburban home that morning before Chris Coleman arrived and discovered the bodies. Shortly after, officers had to restrain the visibly upset man in his yard.

Chris Coleman worked security for Joyce Meyer Ministries, a Fenton, Mo.-based evangelical Christian group. Joyce Meyer spokesman Roby Walker said last week that Coleman resigned after an internal inquiry found he failed to follow a ministry policy.

Walker would not say what policy Coleman allegedly violated.