NEW DELHI, Feb. 12 (Xinhua) -- Indian aviation authorities have launched a probe after a mid-air collision between two passenger planes was averted near Mumbai.

The incident took place on Feb. 7 when an aircraft of private passenger airline Vistara came dangerously close to a plane of India's national carrier Air India in Mumbai's airspace.

"The Aircraft Accident Investigation Bureau has started an investigation as both the carriers were just 100 feet away and were full with passengers," an aviation official said Monday.

While Vistara's flight from the Indian capital to western city of Pune near Mumbai had 152 passengers on board, the Air India flight to Bhopal in central India was carrying 109 people.

Vistara has, meanwhile, said both the pilots involved in the incident have been grounded.

"In this incident, the resolution advisory got triggered due to conflicting traffic. Our pilot followed the standard operating procedure to avoid it," a Vistara spokesperson said.

"The matter is under investigation by the relevant authority," the spokesperson added.