Authorities in Vietnam and Malaysia confirmed on Monday that a yellow object detected at sea off Vietnam and samples of oil slick off Malaysia are not from missing Malaysia Airlines flight MH370.
"The object has been identified as a moss-covered cap of a cable reel" based on a lab analysis, the Civil Aviation Authority of Vietnam said on its website.
The note said the object was found at 3.20pm local time on Monday, along with 637 objects in the area. The object was spotted by Vietnamese air crew 130km south-west of Tho Chu island off Vietnam.
An oil slick was also seen about 185km north off Malaysia's east coast state of Kelantan.
But results of a lab analysis done on the oil samples came back negative for jet fuel.
"The oil is not used for aircraft," Malaysia's Maritime Enforcement Agency spokesman Faridah Shuib told Agence France Presse, adding that it was a type used by ships.
Meantime, Malaysian authorities met with Chinese government representatives to brief them on developments of the search operations and to coordinate bringing families of the 152 Chinese passengers on board MH370 to Kuala Lumpur.
Acting Transport Minister Hishammuddin Hussein, speaking at a news conference, said the Chinese side "made positive comments and had seen what we have been doing".
He dismissed speculation that the holders of the two stolen passports were Chinese citizens, reiterating that investigations were still being conducted by local and international agencies.
"We are working with international agencies on the biometrics, backgrounds fingerprints, and even mental health of the imposters," said Datuk Seri Hishammuddin.
There is intense international attention on how two passports stolen in Thailand up to two years ago were used to buy two plane tickets on flight MH370.
Two men - Italian Luigi Maraldi and Austrian Christian Kozel - came forward to say they were not on flight MH370 despite their names appearing on the manifest.
Late on Sunday, Home Minister Ahmad Zahid Hamidi said the two passengers who used the stolen passports were of Asian appearance. He was questioned on Monday on whether airport security had failed.
The Star Online reported federal police chief Tan Sri Khalid Abu Bakar as saying one of the two suspects who boarded flight MH370 have been identified but refused to divulge the suspect's nationality.
Former prime minister Dr Mahathir Mohamad, when asked if there was a security lapse at KLIA, said: "No, I think they have done their very best. Pointing fingers at them will not help. Every incident teaches a lesson. It's up to them."
Search operations are still ongoing and currently involves 34 aircraft, 40 ships, and more than 100 men. Air search is being conducted from 7am to 7pm daily while sea-borne searches are conducted round the clock.
Malaysia said the search would go on until a decision is made to call it off.
Flight MH370 to Beijng lost contact with Subang Air Traffic Control 50 minutes after departing KLIA at 12.41am on Saturday. The plane did not issue a distress signal nor was there bad weather when it disappeared.
The flight was carrying a total number of 239 people - comprising 227 passengers (including 2 infants) and 12 crew members.
Passengers from 14 nations and Taiwan were on board, the majority being Chinese nationals and Malaysians. No Singaporean was on board.
Flight MH370 was operated on a Boeing 777-200 aircraft, a codeshare with China Southern Airlines.