BURLINGTON, Vt. — Federal and state law enforcement officials are warning that heroin use is once again on the rise in Vermont.

Vermont’s United States Attorney Tristam Coffin and the father of a 21-year-old University of Vermont student who died last year of a heroin overdose held a news conference on Tuesday where they unveiled a new public service announcement warning of the dangers of heroin.

The announcement features Skip Gates, of Skowhegan, Maine, whose son Will died in Burlington in March of last year.

The event coincided with the guilty pleas in federal court of the two men who brought the heroin into Vermont that killed Will Gates.

The public service announcement will begin airing this summer.