(Reuters) - A team of scientists said in a report on Friday that they had found the strongest evidence yet linking a devastating mud volcano in Indonesia to drilling at a gas exploration well by local energy firm PT Lapindo Brantas.
Lapindo has denied triggering the disaster through its drilling activities, arguing the mud volcano near Indonesia's second-biggest city of Surabaya was triggered by an earthquake.
The hot mud started spewing from the East Java drilling site in 2006 and has now displaced nearly 60,000 people.
A scientific team led by Richard Davies of Britain's Durham University said data released by Lapindo provided new evidence indicating that drilling caused the disaster.
"We found that one of the on-site daily drilling reports states that Lapindo Brantas pumped heavy drilling mud into the well to try to stop the mud volcano. This was partially successful and the eruption of the mud volcano slowed down," Davies said in a statement.
"The fact that the eruption slowed provides the first conclusive evidence that the bore hole was connected to the volcano at the time of eruption."
The team led by Davies had previously said in 2008 that it was almost certain drilling caused the disaster.
Mark Tingay, a member of the team who is based at Australia's Curtin University, disputed Lapindo's assertion that mud flow was partly triggered by an earthquake in the Central Java city of Yogyakarta two days earlier.
"The earthquake they claimed was responsible had trivial impact because of the distance" between Yogyakarta and the disaster site, he told Reuters by telephone. Yogyakarta is over 250 km (155.3 miles) south west of the mud volcano site.
Lapindo vice president, Yuniwati Teryana, said the research was wrong.
"They don't have complete data. There is no correlation between the mud eruption and Lapindo," she said, adding Lapindo's view was supported by a decision by Indonesia's Supreme Court in 2009 when it dismissed a lawsuit over the disaster.
"In the court we had several witnesses, including those for and against, who gave their opinion. We should all respect the court result."
Indonesian police also stopped last year a criminal investigation into whether drilling cause the disaster, citing a lack of evidence.
Teryana said Lapindo had already spent 6.3 trillion rupiah ($672.7 million) compensating those affected by the disaster.
The mud volcano has been particularly embarrassing for the government of President Susilo Bambang Yudhoyono, since Lapindo is linked to the Bakrie Group, controlled by the family of Indonesia's former Chief Welfare Minister Aburizal Bakrie.
Bakrie, a powerful businessman, is no longer a minister but is the current head of the Golkar Party, which is part of coalition in parliament supporting Yudhoyono.