NASHVILLE, Tenn. -- Nashville police were asked to search for Vince Young on Monday evening after family members placed a call to the Tennessee Titans informing them of their concern about the quarterback's state of mind.

According to Nashville Metro Police spokesman Don Aaron, Young "abruptly" left his home in Williamson County about 7 p.m. Monday without his cell phone. Those with him at his home, including family members, were "concerned with his emotional well-being," Aaron said.

Police issued a bulletin to all on-duty officers to be on the lookout for Young, and negotiators were placed on standby, a procedure that is common in such situations, Aaron said.

Someone contacted coach Jeff Fisher out of concern for Young, and Fisher contacted the police department, police said.

"I was given some information from people that were close to him late afternoon, early evening that was quite honestly very concerning to me. I'm not going to go into specifics, but it was concerning to me," Fisher said.

In a statement, the Titans said that the smart move was to contact authorities.

"Not having all the facts available to us and approaching the matter prudently, we contacted Metro Police to make them aware of the situation and asked for their assistance in locating Vince," the statement said. "He was located at a friend's house, where we made contact with him.

"He then came to the practice facility, where it was determined that those initial concerns by his friends and family were unfounded and he returned home without incident," the Titans said.

Young left the facility by himself in his own vehicle after speaking with Fisher and officers, police said.

Details were first reported on the Web site of WKRN-TV in Nashville, an ABC affiliate.

Later Tuesday, Young's agent told The Associated Press there was no need for concern because Young had been at a friend's house watching football and eating chicken wings.

"When people were worried about him, I was on the phone talking to him," agent Major Adams said. "I didn't know there was any confusion about where he was as if he was missing or whatever. He just said, 'Hey, I'm over here watching the game.' Then I start getting all these frantic calls."

Adams spoke while on his way to learn the test results on Young's knee, AP reported. Young hurt his knee in Sunday's season opener.

Aaron said there was an unloaded handgun in the glove compartment of Young's vehicle. But as it is not against the law in Tennessee to transport an unloaded firearm with no ammunition present, it was not an issue for the police department, he said. He could not say whether the gun was registered because it was not traced.

Young was booed in Sunday's victory over Jacksonville and did not finish the game because of an injury to his left knee. The Titans said on Tuesday that he has a sprain of the medial collateral ligament, but the team did not set a timetable for his return. ESPN's Chris Mortensen reported on Sunday that Young will miss two to four weeks.

After throwing an interception in the fourth quarter, Young was late to join the offense for its next series, creating speculation that he tried to take himself out of the game after throwing what was his second pick. He sat on the bench after that interception, seemingly unmoved by players and coaches who tried to console him, often holding his head in his hands.

Fisher explained Monday that the issue was tightness in Young's hamstring and that there wasn't clear communication on the sideline about his ability to return to the field. Young did return, but he injured his knee four plays later.

Some, including his mother, question Young's desire to return to the game after the recent incidents.

"What would you think, if you were tired of being ridiculed and persecuted and talked about and not being treated very well, what would you do? What kind of decision would you make?'' Young's mother Felecia Young told The Nashville Tennesssean on Tuesday. "He may not want to deal with it [all], but you have to get to that point before you make that decision first.

"But we're not talking about football right now. We're talking about what would make him happy, and that is the most important thing. ... You don't want people to be hurting like he is. But it is a growing-up process, and he will eventually come out like gold no matter what. But Vince is going to be OK. We are just going to try and give him some space."

Veteran Kerry Collins is the only other quarterback on the roster, but the Titans agreed to terms with free-agent quarterback Chris Simms on Tuesday.

Simms was flying to Nashville on Tuesday night after visiting Kansas City earlier in the day.

Tennessee had worked out Quinn Gray on Tuesday. The team also was looking at QB Joey Harrington and a handful of receivers, including Glenn Martinez and Chad Jackson.

Paul Kuharsky covers the AFC South for ESPN.com. Information from ESPN's Chris Mortensen and The Associated Press was used in this report.