Thai police seized explosives being sent to neighbouring Myanmar to arm protesters following two months of bloodshed.

The weapons included grenades, explosives and ammunition in packages intercepted in Chiang Rai, northern Thailand, on March 28.

Officers said a delivery service had reported the four suspiciously heavy boxes being sent from Chonburi province to be delivered in politically-unstable Myanmar.

Police Colonel Phiphat Naradet, director at Mae Sai police station, led the team of policemen and explosive ordnance disposal to examine the boxes.

The cop said: ‘Our intelligence was that the weapons possibly came from South Korea and were transported by ship before arriving in Thailand. They were supposed to be delivered to a group of minorities in the neighbouring country.

‘Our team traced the addresses and telephone number of a sender. However, the receiver in Myanmar has not been identified yet.’

Thai national Manokorn Sangsorn, 30, and a driver, Songsak Sirichairungrueng, were both later arrested after allegedly arriving to collect the boxes.

Both denied their acknowledgement of what was inside the boxed claiming that they were only hired to do the job and believed the packages were legal.

The weapons were seized following clashes between protesters and soldiers in which more than 100 people were killed on Saturday (March 27).

The violent crackdown by security forces was the deadliest day since protests erupted across the country over the ousting of former leader Aung San Suu Kyi in a military coup on February 1.

Mandalay was one of the hardest-hit areas with more than 10 deaths. At least 114 civilians were killed in 44 towns and cities across the country, including a five-year-old child gunned down in the street. It happened when the military celebrated its annual Armed Forces Day.

A 13-year-old girl was among those killed when the junta’s armed forces opened fire in residential areas of Meikhtila, in Mandalay. At least 20 minors have reportedly been killed since the start of the unrest.

International pressure on Myanmar, still also known as Burma, has escalated with the U.S. government putting sanctions on the country to strengthen its response to the military coup.

Burma was governed by Britain from 1824 to 1948, during which time it became the second-wealthiest country in Southeast Asia but following independence was ruled by the military until 2011 when democratic reforms began.

It changed its name to Myanmar and Aung San Suu Kyi later took over as leader before being widely praised for introducing democratic reforms against ongoing opposition from the military.