India's aviation safety watchdog said on Tuesday surveillance conducted on Air India's Boeing 787 fleet did not reveal any major safety concerns, days after one of its jets crashed, killing at least 271 people.

The aircraft crashed into the campus of a medical college in Meghaninagar moments after taking off from Sardar Vallabhbhai Patel International Airport at 1:39 pm on June 12, killing 241 out of 242 on board as well as 29 on the ground.

There have been cases of a very small number of survivors in very serious accidents, but it is "very rare" for there to be only one, a professor told Newsweek.