Trainer Saffie Joseph Jr., who was suspended after two of his horses died in the lead up to last month's Kentucky Derby, has been reinstated after necropsy reports found no banned substances in the horses, Churchill Downs said on Friday.

Joseph-trained four-year-old filly Parents Pride and five-year-old gelding Chasing Artie collapsed and perished following races at the famed Louisville track in late April and early May.

Churchill Downs Inc. (CDI) said Joseph would be allowed to enter horses in races and apply for stall occupancy at its racetracks "effective immediately" following the release of the Kentucky Horse Racing Commission (KHRC) report.

"We remain deeply concerned about the condition of Parents Pride and Chasing Artie that led to their sudden death," said Bill Mudd, president and chief operating officer of CDI.

"However, given the details available to us as a result of the KHRC investigation, there is no basis to continue Joseph's suspension."

Twelve horses died in a span of six weeks at Churchill Downs, including seven in the week leading up to the first leg of the Triple Crown, which was won by Mage on May 6.

Investigations by the Horseracing Integrity and Safety Authority, Churchill Downs and the KHRC have yet to identify a reason for the fatalities.

Churchill Downs earlier this month announced that the remainder of its Spring Meet, which concludes on July 3, would be moved to Ellis Park in Henderson, Kentucky while investigators conduct a "top-to-bottom" safety review.

(Reporting by Rory Carroll in Los Angeles; Editing by Ken Ferris)