Kenyan human rights activist Boniface Mulinge Muteti has been found alive, four days after he went missing in Nairobi. He was found early Friday in the Lukenya area of Machakos County and is now being treated in hospital.

Hussein Khalid, head of the rights group Vocal Africa, said Muteti was left in the Lukenya area at around 3 a.m. He then walked a long way until he reached a petrol station. A stranger there let him use a phone to call his brother.

"He is disoriented, weak and injured. He is currently receiving treatment at Sanel Hospital in the Mlolongo area. Family, friends and comrades are proceeding there," Khalid said.

Muteti's brother told Citizen TV the activist had been rushed to hospital for treatment. His exact injuries have not yet been made public, and it is still not clear what happened to him during the days he was missing.

Muteti went missing on Monday, Sept. 21. He had reportedly left fellow activists in Nairobi's city centre to go print a petition they planned to hand to police and other government offices. His family said he had been in touch with his colleagues shortly before his phone stopped working.

His disappearance worried his family and fellow activists, who reported the matter to police at Central Police Station in Nairobi and asked for urgent help finding him.

On Thursday, a court petition was filed at Milimani Law Courts asking Inspector General of Police Douglas Kanja and DCI Director Mohamed Amin to explain where Muteti was. In that petition, a colleague said Muteti had been "arrested" on or around Sept. 21, though the circumstances have not been explained. The disappearance was linked to plans for a protest in Nairobi that had been reported to police in advance.

His disappearance had followed protests in Nairobi over the continued detention of Ugandan opposition leader Kizza Besigye.

Since Muteti's recovery, Khalid has raised concern over another activist, Collins Otieno, who he says is now also missing. "Where is our comrade Collins Otieno??? Activism and human rights defence are not a crime. We demand his immediate release," Khalid said.

Police have not publicly said whether Muteti was in their custody at any point, and the full circumstances of his disappearance remain unclear.