NAIROBI -- Protesters in Kenya on Tuesday broke through security at the parliament building in Nairobi, capital of Kenya, and stormed the institution just hours after lawmakers passed a contentious tax hike bill.

Hundreds of anti-tax hike demonstrators overpowered security guards and entered both the National Assembly and the Senate, where they vandalized the premises.

Part of the parliament building was set on fire by angry protesters, many of whom were chanting anti-government slogans.

Earlier this day, protesters took to the streets to oppose the finance bill that aims to raise taxes on a wide range of items, which they argue will exacerbate the economic hardships faced by citizens.

At least four protesters were shot dead and several others sustained serious bullet wounds during the violent chaos, said Nairobi County Police Commander Adamson Bungei.

"I saw four bodies lying in a pool of blood outside parliament. Things are really sad," a witness told Xinhua outside the parliament building.

Some protesters had brought down a gate near the Senate and burnt down a police lorry that was outside the parliament.

Members of parliament were evacuated as the group of protesters confronted police.

The finance bill seeks to raise an additional 346.7 billion shillings (about 2.67 billion U.S. dollars) in taxes, including the railway development levy from 1.5 to 2.5 percent and the import declaration fee from 2.5 to 3.5 percent.