Nevada Litfin, a longtime trainer at Canterbury Park, has been suspended by state and federal agencies for alleged violations of anti-doping rules.

In a ruling posted Wednesday, the Minnesota Racing Commission (MRC) said Litfin was observed by the commission's security staff "engaging in acts detrimental to the integrity of racing.'' The Horseracing Integrity and Welfare Unit (HIWU), a federal group that oversees horse racing's anti-doping measures, followed on Thursday with a provisional suspension for alleged violations of several rules.

The HIWU ruling cites a regulation that bans trainers from possessing hypodermic needles or syringes, as well as rules regarding the use or attempted use of a controlled medication method and substance that is not allowed on race day. The MRC notice refers to state rules barring possession of hypodermic equipment and injectable substances, possession or administration of prohibited substances, and cooperation with security officers.

Both rulings say the alleged violation occurred on Aug. 16. The HIWU notice said it involved the horse Dominus Tecum.

Litfin is banned from the Canterbury Park grounds, and horses cannot race under his name. It is unclear what additional penalties he could face. Several of his horses were scratched from Canterbury's races in recent days.

Litfin did not respond to a request for comment.

With 16 winners from 68 starts, Litfin is tied for sixth place in the Canterbury trainer standings. This year has been his best ever, with career highs in purse earnings ($437,296) and win percentage (15%). His 21 overall victories this season tie his career best, set in 2016.