At least 20 people have been killed after a 5.7 magnitude earthquake hit southern Pakistan on Thursday, government officials said.

Many of the victims died when roofs and walls collapsed, Suhail Anwar Hashmi, reports AFP citing a senior provincial government official.

Provincial interior minister Mir Zia Ullah Langau said, “We are receiving information that 20 people have been killed due to the earthquake. However, the death toll may increase Rescue efforts are underway.”

The worst-affected area was the remote mountainous city of Harnai, in Balochistan, where a lack of paved roads, electricity and mobile phone coverage has hampered the rescue effort.

Social media showed houses shaking and light fittings swaying as the quake struck, and later stunned residents gathering in the street in the dark.

The injured were rushed to hospital, while some were treated on stretchers in the street under phone torch light.

The earthquake was also felt in Balochistan’s provincial capital Quetta.

The US Geological Survey said the quake had a magnitude of 5.7 and struck around 3:00 am at a depth of around 20 kilometers.

Pakistan straddles the boundary where the Indian and Eurasian tectonic plates meet, making the country susceptible to earthquakes.

In October 2015, a 7.5-magnitude quake in Pakistan and Afghanistan killed almost 400 people across rugged terrain that impeded relief efforts.

The country was also hit by a 7.6-magnitude quake on October 8, 2005, that killed more than 73,000 people and left about 3.5 million homeless, mainly in Pakistan-controlled Kashmir.

ARR