A total of 19 Hongkongers had been located and confirmed to be safe as of Monday, the department said.

Five others remained missing. The department said it would continue to help their families locate the missing people. 

"Department officers will actively follow up on the cases of those who have lost contact with their families," a spokesman said.

The department has so far received 24 calls for assistance from Hongkongers visiting the country or their families.

Saturday's 7.8-magnitude earthquake spread horror from Kathmandu to small villages and to the slopes of Mount Everest, and triggered an avalanche that buried part of the base camp packed with foreign climbers preparing to make their summit attempts. At least 18 climbers are known to have died, the worst climbing disaster on Mount Everest. At least 61 were injured.

There were terrified screams as the aftershock hit the capital city. At magnitude 6.7, it was strong enough to feel like another earthquake, and came as planeloads of supplies, doctors and relief workers from neighbouring countries began arriving in the poor Himalayan nation.

"The aftershocks keep coming ... so people don't know what to expect," said Sanjay Karki, Nepal country head for global aid agency Mercy Corps. "All the open spaces in Kathmandu are packed with people who are camping outdoors. When the aftershocks come you cannot imagine the fear. You can hear women and children crying."

Watch: Aftershocks keep survivors on edge in Nepal

The earthquake centred outside Kathmandu, the capital, was the worst to hit Nepal in more than 80 years. It destroyed large strips of the oldest parts of Kathmandu, and was strong enough to be felt in India, Bangladesh, Tibet and Pakistan.

By the evening, the death toll had grown to more than 2,300 people, including four Chinese. With search and rescue efforts far from over, it was unclear how much the death toll would rise.

The aid group World Vision said remote mountain communities were totally unprepared.

Some villages near the epicentre were "perched on the sides of large mountain faces and made from simple stone and rock construction. Many of these villages are only accessible by 4WD and then foot, with some villages hours and even entire days' walks away from main roads at the best of times", said the group's local staff member, Matt Darvas.

Nepal's worst recorded earthquake, in 1934, measured 8.2 and all but destroyed Kathmandu, Bhaktapur and Patan.

Yesterday, most areas were without power and water. The United Nations said hospitals in the Kathmandu Valley were overcrowded, and running out of supplies and space for corpses.

Most shops in Kathmandu were shut - only fruit vendors and pharmacies were open.

With Kathmandu airport reopened, the first aid flights began delivering supplies. China was among the first to respond, along with India and Pakistan.

A 62-strong China International Search and Rescue Team arrived in Kathmandu, while Indian air force planes landed with 43 tonnes of relief material, including tents and food, and nearly 200 rescuers.

Among the buildings destroyed in Kathmandu was the nine-storey Dharahara Tower, a landmark built by Nepal's royal rulers as a watchtower in the 1800s and a Unesco-recognised historical monument.

It was reduced to rubble, and there were reports of people trapped underneath.

How to help

HSBC : 500-334149-010/ Hang Seng bank account: 267-175123-009/ Bank of China bank account: 012-806-00034033

HSBC: 001-6-331860/ Bank of China: 012-874-0-010515-7/ Hang Seng Bank: 284-401080-003

HSBC: 567-354014-005/ Bank of China: 012-875-0-021868-3/ Wing Lung Bank: 020-601-003-7634-8/ Bank of East Asia: 015-260-81-012100

HSBC: 018-377077-003/ Hang Seng Bank: 286-364385-005/ Bank of China: 012-883-0-002136-6