Myanmar has been in turmoil since the generals toppled Aung San Suu Kyi's civilian government two years ago, ending a brief democratic experiment and sparking mass protests.

The army has used artillery barrages as well as air strikes against opposition groups as it struggles to crush resistance, according to rights organisations, sparking international calls to stop supplying weapons to the junta.

In October, state-owned arms manufacturer Yantra India Limited sent 20 gun barrels to Myanmar measuring 122 millimetres, shipping data obtained by activist group Justice for Myanmar shows.

The consignee for the cargo, which was valued at $330,000, was Innovative Industrial Technologies Company Limited, based in the commercial hub Yangon, according to the data shared with AFP.

Last year, the same company won a junta tender to install and configure security appliances at a data centre, according to documents seen by AFP.

The barrels were likely used to make artillery for the military, Justice for Myanmar said.

Yantra India Limited has "state-of-the-art steel-making" facilities for gun barrels and "other components of artillery and tank guns", according to its website.

AFP has approached Yantra and Innovative Industrial Technologies for comment.

"India is directly supporting the junta's indiscriminate attacks against civilians by allowing the export of barrels," said Justice For Myanmar spokesperson Yadanar Maung.

More than 3,000 people have been killed in the military's crackdown on dissent, according to a local monitoring group.

Diplomatic efforts to resolve the crisis have floundered, with the junta shielded at the United Nations by close allies Russia and China.

In December, India abstained -- along with Moscow and Beijing -- from the UN Security Council's first resolution on the crisis, which called for the release of all "arbitrarily detained" prisoners, including Suu Kyi.

Indian Foreign Minister S. Jaishankar has defended New Delhi's ties with the junta, saying India cannot avoid dealing with its neighbour because of cross-border issues such as organised crime.

In January, Norway's sovereign wealth fund said it had divested its shares in Indian state-owned company Bharat Electronics over an "unacceptable risk" that it was selling weapons to the Myanmar junta.