Massive search for the missing Malaysian plane will be expanded to scour mountainous and forest areas, said Lieutenent Gen Vo Van Tuan, Deputy Chief of the General Staff of the Vietnam People's Army.
"We have informed units and localities on land, including Military Zones 5, 7 and 9, and localities in the western, southeastern and central regions, to deploy forces to find the plane," Tuan said on Tuesday.
Units managing border areas were requested to increase coordination with Lao and Cambodian forces, he said.
Earlier, two hotlines were set up at the command office in Phu Quoc Island, southern Kien Giang province to provide information relating to the search.
Transport Deputy Minister Pham Quy Tieu said at a press conference in Phu Quoc on Tuesday that Vietnamese forces would continue the operation on a wider area.
The search will be expanded to the east of the initially suspected area, 277km from Tho Chu Island in Kien Giang province, and the south and west of Con Dao Island, 185km off the coast of the southern province of Ba Ria-Vung Tau.
The Phu Quoc International Airport would also be used as a base for rescue efforts.
The naval ship HQ888 had examined waters off southern Ba Ria Vung Tau province without finding any fragments spotted by a Hong Kong commercial aircraft on Monday, according to the National Committee for Search and Rescue.
At 11am on Tuesday, the VNRedsat-1 satellite passed over Tho Chu Island and captured images there for about an hour.
Four aircraft took off to search for the Malaysian plane.
Vietnam's air force will continue to conduct a number of flights to suspected sites during the day, said Colonel Tran Van Lam, deputy head of Air Division 370.
China has deployed 10 satellites aimed to provide reliable positioning signals for the search operation.
It also sent two naval vessels, Jinggangshan and Mianyang, to the target sea area and plans to deploy two more.
According to the US Navy, it has dispatched one more Arleigh Burke-class guided-missile destroyer, USS Kidd, to the waters around the Malaysian jetliner's last known location, in addition to the USS Pinckney to mount search efforts.
On Monday, Boeing said that it would work as a technical consultant for the US National Transportation Safety Board's ongoing search mission in Southeast Asia. (***)