BANGKOK (REUTERS) - A Thai defence ministry looking into allegations of corruption at a military-built park said on Wednesday (Dec 30) it had found financial "irregularities" in the project but had no authority to investigate any wrongdoing.

Rajabhakti Park was built to honour Thailand's much-revered monarchy, but has become a lightning rod for anti-junta sentiment and a potential embarrassment to a military that seized power last year vowing to crack down on graft.

Sitting on army land in the royal resort town of Hua Hin, the project was overseen by General Udomdej Sitabutr, a former army chief who is currently deputy defence minister.

"We have noted irregularities which we will pass on to the defence minister, the prime minister and relevant agencies,"said General Chaicharn Changmongkon, deputy permanent secretary for defence, who headed the inquiry.

He would not elaborate on what those irregularities were, and told reporters the inquiry's "limited authority" meant it was unable to identify any wrongdoers.

More than 63 million baht (S$2.47 million) out of the park's total budget of 866 million baht was drawn from the state, said Chaicharn, contradicting previous military assertions that no government funds had been used.

The military overthrew an elected government in May 2014, and experts say its popular acceptance relies heavily upon a carefully cultivated reputation for battling corruption.

This has made the junta acutely sensitive to graft allegations at Rajabhakti Park levelled by some Thai media and opposition groups.

Police and soldiers intercepted a train on Dec 7 and disconnected a carriage carrying anti-junta activists to the park and briefly detained dozens of people.

Police later vowed to charge 11 of the activists for illegal assembly. Gatherings of more than five people are banned under the junta.

The military had a week earlier stopped two leaders of the United Front for Democracy Against Dictatorship, a group aligned with politicians who have challenged the old military-linked establishment, from visiting the park, which features giant statues of past Thai kings.

Two people were detained in December on suspicion of sharing an infographic on Facebook alleging corruption at the park.

An earlier military inquiry into the project found no evidence of wrongdoing.

However, Udomdej said on Nov 10 there was "an element of truth" to allegations that an unidentified civilian had demanded bribes from foundries that cast the statues.