A well-known critic of the Laos government has been shot dead in a late-night attack in the capital.

Anousa 'Jack' Luangsuphom, 25, was shot point blank in the face and chest while sitting at a coffee shop on Saturday.

He had run the Kub Kluen Duay Keyboard (Driven By Keyboard) Facebook page, where people dared to expressed criticism of the Communist authorities.

Rights groups have condemned officials for not yet announcing an investigation into the brazen "cold-blooded killing".

Security cameras captured the attack. Footage shows a gunman dressed in a brown long-sleeved shirt and black cap entering the cafe and firing twice at Luangsuphom, who is seated on the floor, before fleeing.

He died on the way to hospital.

The young activist had been "one of the few people in Laos who regularly and openly expressed views that were critical of the government", Human Rights Watch (HRW) said.

"(This) sends a spine-chilling message that no one in Laos who criticises the government is safe," said the group's Asia director Elaine Pearson.

HRW also condemned the Lao government's "apparent apathy" towards seeking justice for the activist's killing.

The government has not yet responded to criticisms. Mr Luangsuphom's killing has been reported on in local media.

HRW says Lao authorities have often not responded adequately to attacks against government critics, human rights defenders, and political activists.

It noted the "enforced disappearance" of activist Sombath Somphone, whose whereabouts remain unknown more than 10 years after he was taken into police custody in Vientiane.

HRW also cited the case of Od Sayavong, a Lao activist living in Bangkok, who has been missing since August 2019.

Government officials had denied any knowledge of both disappearances.

There is little room for political opposition or dissenting voices in Communist-ruled Laos, one of Asia's poorest countries.

The landlocked country between Thailand and China is a one-party state, ruled by the Lao People's Revolutionary Party, where "authorities use legal restrictions and intimidation tactics against state critics", says the US political advocacy group Freedom House.