London - Chelsea announced on Tuesday they have sacked a player who let off a smoke grenade at their training ground.
The Blues said they had "parted company" with 21-year-old Jacob Mellis, who played once for the first team, following a "full and thorough" investigation into the incident on March 2.
Midfielder Mellis's team-mate, Billy Clifford, escaped with a fine after admitting to bringing the grenade into Chelsea's training ground in Cobham, south of London.
Clifford, 19, is a regular in Chelsea's reserves and signed a new four-year deal last year.
Mellis, 21, joined Chelsea from Sheffield United five years ago and made his debut in the Champions League win against Zilina in November 2010.
In setting off the grenade in the reserves' dressing room, Mellis triggered a full-scale evacuation procedure, with players and staff rushing from the building because of thick smoke.
It was not the first controversial incident at Cobham, with Chelsea and England defender Ashley Cole accidentally shooting and wounding a work experience candidate there with an air rifle in February last year.
Cole, it is believed, did not know the rifle was loaded and he subsequently apologised to the student.