Vietnam said several large fragments were spotted in waters off southern Ba Ria Vung Tau province late Monday, as the search for a missing Malaysian jet continued.

According to Vietnam’s National Committee for Search and Rescue, late Monday afternoon, China’s Hong Kong Air Traffic Management Division informed them that a passing Hong Kong commercial aircraft spotted several large fragments in waters some 32 nautical miles (60 km) southeast of O Cap cape in southern Ba Ria Vung Tau province, local online newspaper VNExpress reported.

Le Van Chien, director of Vung Tau port authorities, told VNExpress that concerted efforts have been made to find the fragments and determine whether they come from Malaysia Airlines Flight MH370, which vanished en route to Beijing from Kuala Lumpur Saturday morning with 239 people on board.

As there are many fishing boats operating in the area, Vung Tau port authorities have informed border guards, naval ships and fishing boats in the area to coordinate searching for the fragments, said Chien.

Local online newspaper Thanh Nien (Youth) on Monday also quoted Chien as adding that, as soon as receiving the information on the fragments, a Thai container vessel which was on its south-north route was asked to search from 17:30 to 18:00 local time (1030 to 1100 GMT). However, the ship failed to find any fragments.

Vung Tau port authorities pointed to the possibility that the fragments could be pieces of foam or nylon that fishermen had left while fishing there, said Chien.