A Texas man who went missing as a teenager in 2015 after last being seen walking his dogs in Houston has been found alive, his family and police said.

Police and firefighters found Rudolph “Rudy” Farias IV around 10pm on Thursday after getting a call of a person being down in front of a church in south-east Houston, police spokesman John Cannon said.

It was not immediately known where Mr Farias had been the last eight years, Mr Cannon said. Police investigators had not yet spoken with Arias, 25, who remained in hospital.

“What we do know is at the time of his recovery, a good Samaritan located him unresponsive and immediately called police and 911. My son Rudy is receiving the care he needs to overcome his trauma, but at this time, he is nonverbal and not able to communicate with us,” Janie Santana, Mr Farias’ mother, said in a statement.

In a tweet on Monday afternoon, Houston police said it planned on speaking with Mr Farias and his family on Wednesday.

The news that Mr Farias had been found was first reported in a tweet on Saturday by the Texas Centre for the Missing, which was handling public communications on behalf of Mr Farias’ family.

“We do know when a loved one goes missing this is the day all families hope for and dream of – reunification. We are thankful that Rudy has been found and receiving the care he needs,” the centre said in a statement on Monday.

Mr Farias was 17 years old when he was reported missing on March 6, 2015, after taking his two dogs for a walk near his family’s home in north-east Houston. The dogs were later found.

Houston police, along with Texas Equusearch, a civilian search and recovery team, looked for Mr Farias but found no signs of him.

When Mr Farias first went missing, Texas Equusearch reported that he suffered from depression and anxiety, and he might have been disoriented because he was not taking his medication.

Mr Farias also had asthma and walked with a slight limp because of an injured right leg.

“According to his mother he is very wary around strangers,” Texas Equusearch said in 2015.

Mr Cannon said Mr Farias’ family did report to police investigators that they had seen him in September 2018, staying behind the home of a relative.

Police investigators followed up on the 2018 sighting and went to the relative’s home. But “they could not observe him. They could not locate him,” Mr Cannon said.

Since police were not able to find Mr Farias after the 2018 sighting, the investigation remained open as a missing person case, Mr Cannon said.

Ms Santana and other family members were not available for comment on Monday.

“We are asking for privacy during this difficult time but will share more details as Rudy continues to heal,” Ms Santana said in her statement.