NAIROBI, Kenya -- Kenya's finance minister has been arrested on charges of fraud and corruption over contracts for the construction of two dams in western Kenya, a top police official said Monday.

Finance Minister Henry Rotich gave statements to police at the criminal investigation headquarters and is expected to be charged in court Tuesday, Kenya's director of criminal investigations George Kinoti said.

Rotich and 27 other officials were arrested and charged for their alleged roles in awarding contracts and payments to the Italian firm CMC di Ravenna, said the director of public prosecutions Noordin Haji. Many procurement procedures stipulated by the law for such projects were ignored and the law was circumvented to ensure that CMC di Ravenna got the contracts while it was facing liquidation back home in Italy, he said. The cost of building the two dams was inflated by about $164.5million, said Haji.

"The national treasury negotiated a commercial facility increasing the amount to approximately $608 million (63 billion Kenyan shillings) which is $164.5 million (17 billion Kenyan shillings) more than necessary," Haji said. The two dams, Kimwarer and Arror, are planned for Kenya's Elgeyo Marakwet county but have not yet been built.

Rotich and CMC di Ravenna both deny wrongdoing.

Haji said CMC di Ravenna submitted draft technical designs for construction of the two dams in February 2019, four years behind schedule. He said an insurance company was paid $106 million upfront to guarantee the project, which was unnecessary as the government could have acted as guarantor at no cost, said Haji.

Kenya's leading anti-corruption crusader, John Githongo, welcomed the arrests.

"This is a most interesting development. I hope that it's treated differently than similar cases before in the fight against corruption that caused excitement then fizzled out," Githongo told The Associated Press. Very few convictions have been made of prominent people charged with corruption and those convicted spent less than two years in jailed, he said.

Kenya is considered to have a serious corruption problem, ranked 144 out of 180 nations by Transparency International in its annual corruption index. Rotich, the finance minister, is an ally of Deputy President William Ruto. Ruto in February defended the payments made for the dams saying "no money will be lost." Many local commentators say this is sign of a falling out between Kenyatta and Ruto.

It is the first time a Kenyan finance minister has been charged while in office. Two others were charged after they had left office.

President Uhuru Kenyatta has made several public promises since his re-election in 2017 that he will tackle corruption, which is widely viewed as endemic in all levels of society here. Many however remain skeptical of Kenyatta's pledges. In late 2015 Kenyatta declared corruption a national security threat and promised to investigate all customs and revenue officers. The vetting has yet to take place. In the streets, despite all the talk, Kenya's police routinely solicit bribes from motorists and commuters.