China on Monday asked Malaysian authorities to step up search efforts and investigation into the missing Malaysia airlines flight, saying it had become a race against time.
But relatives of the 151 Chinese passengers onboard said they were frustrated with all sides of the rescue effort.
In a telephone conversation with Malaysian Prime Minister Najib Razak, Premier Li Keqiang urged Kuala Lumpur to step up investigations with all-out efforts and try their best to comfort the families of the passengers on board the flight.
The state-run Global Times newspaper said the Malaysian side "cannot shirk its responsibilities."
"The initial response from Malaysia was not swift enough. There are loopholes in the work of Malaysia Airlines and security authorities," it said.
Read: Relatives of passengers hover between despair and fragile hope
The newspaper wanted Malaysia Airlines to own up blame if the plane's disappearance occurred because of a deadly mechanical breakdown or pilot error.
"If this is a terrorist attack, then the security check at the Kuala Lumpur airport and on the flight is questionable," it added.
But on Monday morning it was Chinese government officials who were in for a rough time when they visited the east Beijing hotel where families and friends of the passengers are staying.
They were confronted by relatives who said the Chinese government was doing little to help them.
Director general of Civil Avition Department (DCA) Azharuddin Abdul Rahman explains to journalists regarding the new search and rescue areas during a press conference in Sepang. (AFP photo)
Reports said some angry family members hurled plastic bottles at the officials, calling them "useless government".
Nearly two-thirds of the 239 people aboard Malaysia Airlines (MAS) flight MH370 were from China, and if the loss of the aircraft is confirmed, it would be China's second-worst air disaster in history.
Later in the day, the foreign ministry tried to calm tempers down by saying that the government was pushing Malaysian government to do more.
"China has requested the Malaysian side to step up efforts and investigation and provide information to China in a timely fashion," foreign ministry spokesperson Qin Gang told a regular press briefing on Monday.
He said the Malaysian side was mainly responsible for search and rescue missions and China was cooperating with them in every possible way.
"We hope that the Malaysian side will fully understand the emergent mood of the Chinese family members of the passengers," Qin said.
Read: China sends investigators to Malaysia to probe terror link
He said the task force from China arrived in Malaysia in the afternoon to assist local authorities in investigation.
He said the China's ministry of public security, responsible for the country's internal security, decided to send the team to Malaysia after Interpol confirmed two stolen passports were used by two persons to board the aircraft.
The Malaysian authorities have sent a team to Beijing to update family members waiting in Beijing.
China deploys 10 satellites to strengthen search efforts
As the mystery over the missing plane deepens, China pressed 10 high-resolution satellites to scurry South China Sea to find leads that could help locate the flight with 239 people on board.
China's Xi'an Satellite Monitor and Control Center has launched an emergency response for the search and adjusted up to 10 high-resolution satellites to locate the missing plane which is presumed to have crashed on Saturday, the People's Liberation Army said.
Citing the Centre, the army said the centre purged the original commands of several satellites to offer full services in weather monitoring, communication and other aspects for the search, state-run Xinhua news agency reported.
A Chinese relative of passengers aboard a missing Malaysia Airlines plane cries while leaving a hotel room for relatives or friends of passengers aboard the missing airplane, in Beijing. (AP photo)
Read: Probe into missing Malaysia jet looks at possible mid-air disintegration
The China Daily newspaper wrote in an editorial that "terrorism cannot be ruled out".
"The fact that some of the passengers on board were travelling with false passports should serve as a reminder to the whole world that security can never be too tight," it added.
Malaysia's police chief said Monday that one of the men who used the passports had been identified, after ministers reportedly said they had Asian facial features.
At a Beijing hotel, Malaysian embassy officials were processing visa applications for families wanting to take up an airline's offer to travel to Kuala Lumpur to be closer to the rescue operations.
Even as information remains sparse and the hours tick by, many relatives in Beijing continue to believe that the passengers may yet be found, according to one US-trained psychologist who counselled about 20 families awaiting news at the hotel.
"I think most of them are holding onto that thin ray of hope," he said. "Whether they believe it to be realistic or not, most of them are not letting it go."
Read: What could have happened to Malaysia Airlines flight 370