Malaysia's acting transport minister has said that he was informed by the Chinese government that it received new satellite images of possible debris from the missing plane.

Hishammuddin Hussein told reporters in Kuala Lumpur on Saturday that the images showed an object that measures 22.5-by-13 metres.

The new object was reportedly spotted about 120km away from the sightings first announced by Australia last Thursday, according to Al Jazeera's Andrew Thomas, who was reporting from Perth.

The latest announcement came as the hunt for the Malaysian Airlines flight MH370 entered its third week, with the country asking the US to provide undersea surveillance technology and search efforts continuing thousands of kilometres off the coast of Australia.

The Australian Maritime Safety Authority said it would send six aircraft throughout the day on Saturday.

Relatives angry

In Beijing on Saturday, relatives of the passengers were getting increasingly angry, with hundreds of them confronting Malaysian officials.

They said they had not been able to ask the officials about the search efforts.

The families later held a separate news conference to express their frustration.

Search area off the west coast of Australia [EPA]

On Friday, Hussein, who is also the country's defence minister, asked the US for underwater technology.

Chuck Hagel, the US defence secretary, told Hussein that he would contact Malaysian authorities after considering the matter.

Five planes were sent to the southern Indian Ocean on Friday to look for objects that may be from the missing Malaysian jet.

And an Australian official said the hunt would be extended for another day after nothing had been found in the area, about 2,500km southwest of Perth, according to the AP news agency.

"Something that was floating on the sea that long ago may no longer be floating," said Warren Truss, who is the acting Australian prime minister while Tony Abbott is in Papua New Guinea. "It may have slipped to the bottom," he added.

Abbott also said "if there is anything down there, we will find it". 

Search efforts shifted to remote areas of the Indian Ocean after objects were identified on satellite images five days ago.

Efforts have also been renewed in the Andaman Sea between India and Thailand, covering areas that have already been thoroughly swept.

Australian, New Zealand and US aircraft will be joined by Chinese and Japanese planes over the weekend.

Source: Al Jazeera and agencies