The Qantas plane that had its belly torn open when an oxygen tank exploded over Manila has been damaged in a collision with another Qantas plane.

Qantas said the two Boeing 747s collided on the tarmac “during towing” at Avalon Airport’s maintenance base south of Melbourne on Tuesday.

A number of workers have been stood down pending the results of an investigation.

The crash is the latest in a string of safety woes for the national carrier – the most serious in July when one of the 747s involved in today’s incident had a hole blown in its fuselage as it flew over Manila en route from Hong Kong to Melbourne.

Qantas general manager of engineering David Cox said the two planes had “come into contact with each other during towing this morning”.

“Both aircraft did sustain some damage and the extent of this is being assessed,” he said in a statement.

Footage showed damage to the nose cone of one plane, and the other with a damaged wing. No-one was aboard either plane at the time.

A Qantas spokeswoman later refused to comment on the extent of damage, but it was enough for both planes to be grounded.

She would not say how close the plane damaged over Manila had been to returning to service.

“I understand that repairs were being undertaken in Manila by Boeing and Qantas – further work was being done in Avalon prior to its return to service,” she said.

Qantas’ image has taken a battering following the string of recent mishaps, including the dramatic midair plunge of a flight enroute from Singapore to Perth in October.

The plane fell 650 feet in 20 seconds, hurling unrestrained passengers around the cabin.

About 40 passengers were taken to hospital after it made an emergency landing in Learmonth, near Exmouth in Western Australia’s north.

Australian Transport Safety Bureau investigators said an irregularity in one of the plane’s computers may have caused the dive.

A report issued by the Civil and Safety Authority (CASA) in September cleared Qantas of any system-wide failures in its maintenance program.

But it identified “signs of emerging problems” in the airline’s ability to meet internal safety benchmarks.