FERNDALE, Mich. -

Local 4 cameras were rolling as police brought in the murder suspect they've been searching for since Tuesday morning.

Detectives believe the suspect, a homeless man, stabbed a 67-year-old man at his apartment at Devon Square in Ferndale.

"We believe our suspect in this case is obviously pretty heartless and a violent individual," Lt. William Wilson, Ferndale police.

The murder happened Sunday afternoon. Police say the men had become acquaintances. Detectives say the victim was physically and mentally challenged but very friendly. There's a possibility the elderly man took the suspect in trying to help him and the homeless suspect took advantage of that.

Police have video of the suspect going back to the man's apartment -- even after the murder -- to steal a TV.

Investigators say the suspect also stole the man's car but eventually ditched it and returned back to the streets. That's where detectives found him, at his usual begging spot near Interstate 75 and 8 Mile Road.

"A lot of agencies jumped in to help on this investigation," said Wilson.