DAVAO CITY, Philippines - A plane carrying over 120 passengers made an emergency landing in southern Philippines on Friday after smoke was observed inside the aircraft, police said.

Philippine Airlines flight PR-1814 carrying 128 passengers was on its way to Manila from the southern Philippine city of Davao when it returned to the Davao International Airport and made an emergency landing around 1:34 pm, said Antonio Rivera, Southern Mindanao police regional spokesperson.

Rivera told Xinhua the plane of the country's flag carrier was about four minutes into its flight when it turned back after "a smoke came out of its cargo compartment area."

He said a fire truck from the Civil Aviation Authority of the Philippines (CAAP) immediately responded to the site, as well as a medical team to check on the condition of the plane passengers.

An investigation into the incident was now underway, the police spokesperson said.