BOGOTA - Colombian authorities said Monday that two police officers were injured when a police helicopter was blown up by a rebel group in Briceno, in the northwestern province of Antioquia.

An explosive device, planted on the Bell Ranger 206 aircraft, went off minutes after the crew hopped off for a relief, according to provincial government secretary Santiago Londono.

The Revolutionary Armed Forces of Colombia (FARC)'s 36th Front was initially blamed by the authorities for the attack, and a police report with further details will be issued in coming hours.

Antioquia Governor Sergio Fajardo condemned the attack, which occurred during a 30-day ceasefire announced by FARC, beginning from December 15.

"Truce? In Briceno, police helicopters are always blown up," Fajardo wrote in his official twitter account.

According to the National Police, the injured police officers, including a pilot and a technician, are being treated at the Briceno Hospital and will soon be transferred to Medellin, Antioquia's capital.