Two men have pleaded not guilty to charges stemming from the death of a teenage boy at an alcohol-fueled underage party last year in Massachusetts.

Prosecutors say 19-year-old Joseph Zagarella slammed 15-year-old Ethan Costello's head on a concrete floor after Costello bumped into him during a party in Lowell in October 2016. The Tewksbury resident died days later from his injuries.

Zagarella pleaded not guilty Thursday to manslaughter and other charges.

The 51-year-old Thomas Ogden allegedly bought the alcohol for the party, which was hosted by his 15-year-old daughter. He pleaded not guilty to furnishing alcohol to minors.

Prosecutors say the party was supposed to be for about 10 people, but 60 to 80 showed up.

Zagarella's lawyer says her client did not mean to hurt Costello. Ogden refused comment outside court.