A 59-year-old man was found dead in a swimming pool at his Derwood home Saturday in what Montgomery County police are calling an accidental drowning. 

Mojtaba Tehrani Kia, of the 7000 block of Needwood Road, had been doing yard work in his backyard for several hours when a family member looked out a window and saw him lifeless in the pool, police said.

County police and fire and rescue units responded to the call about 3:15 p.m. and tried unsuccessfully to resuscitate Kia, who was pronounced dead at a local hospital, police said.

Kia was wearing swim trunks and his sandals and a towel were found next to the pool, according to police.

Foul play is not suspected, police said. The state Medical Examiner’s Office will determine the cause of death.