Sombre horns sounded at the site of Bangkok’s deadly bomb blast as officials joined a multi-religious ceremony for victims of this week’s attack.

A British national was among those killed in an attack on a popular shrine in Thailand, the UK’s Foreign Secretary Philip Hammond said.

Investigators believe a man seen in security video wearing a yellow T-shirt and carrying a backpack set off the explosion at a central Bangkok shrine that killed 20 people and injured more than 100, Thai police said.

The bombers who killed at least 20 people and injured at least 140 in Bangkok intended to damage Thailand's tourism industry, the country's defence minister said.

UPDATE (5.10pm): An explosion at a popular shrine near a key political protest site in central Bangkok, has reportedly killed at least 16 people and injured dozens of others, officials said.