CHEROKEE COUNTY, Oklahoma - Authorities are concentrating their search Friday for a missing elderly man in the Cookson area.

The sheriff's office issued a Silver Alert Thursday for 73-year-old Alvin Watts of Park Hill.  His family says Watts recently had back surgery and was taking prescription medication for the pain.

Undersheriff JC Chennault said Friday afternoon the search crew found Watts' pickup truck in the south end of Cherokee County near the Adair/Sequoyah County line. 

The team is using search and rescue dogs and will search until dark.