Police in Bangkok say they have arrested one of the suspects in the bombing that killed 20 people earlier this month.
He was found after police raided an apartment in the city’s north and found possible bomb-making materials, national police spokesman Prawut Thavornsiri said.
Mr Thavornsiri said the man arrested matched the description of the main suspect and was foreign but would not confirm his nationality.
He was allegedly captured on security camera footage leaving a rucksack at the site before the blast on 17 August, police say.
The blast happened at 7pm (1pm UK time) near the Erawan Hindu shrine in the downtown Chidlom district – a shopping hub popular among tourists.
Many of those killed were tourists and at least 117 people were wounded, some of whom lost limbs.
CCTV footage showed a huge orange fireball as the bomb exploded and people fleeing down the street.