“The commission considers there is enough evidence to indict Yingluck and refers [the case] to the Senate,” Panthep Klanarongran, chief of the National Anti-Corruption Commission (NACC) told reporters.

If found guilty by the upper house Yingluck could face a five-year ban from politics.

The NACC said is still considering whether Yingluck should face criminal charges, which could see her given a jail term.

Her billionaire elder brother Thaksin Shinawatra, lives overseas to avoid a prison sentence for corruption that he contends was politically motivated in the wake of his ousting by an army coup in 2006.

Thailand remains stuck in a political quagmire with the ailing government staggering on despite a slew of legal challenges and protests on Bangkok’s streets.

Anti-government protesters, who accuse the Shinawatras of poisoning Thailand with corruption, said they would appoint a new government on Friday – a move that would risk further political violence.

“Tomorrow [Friday] we will take steps towards appointing a new government,” protest spokesman Akanat Promphan told reporters earlier, saying the government had lost “all legitimacy”.

The protesters are known for their hyperbolic statements and it was not immediately clear what legal basis their vow was based on.

But Akanat said the Thai constitution has an article that may enable the appointment of a new executive body by the Senate.

The appointment of a new premier by the anti-government group “is the red line not to be crossed,” said Thailand-based author and academic David Streckfuss.

“The red shirts will rise en masse,” he said referring to Shinawatra supporters who are due to hold a mass rally on Saturday in a Bangkok suburb.

The NACC’s decision comes a day after the Constitutional Court removed Yingluck from office for abusing her power in the 2011 transfer of a security official.

The ruling Puea Thai party swiftly appointed a deputy premier and commerce minister – Niwattumrong Boonsongpaisan – as Yingluck’s replacement and vowed to push for new elections on July 20 to cut a path through the turmoil.

Watch: Thailand gripped by political turmoil

‘Judicial coup’

Yingluck was intially accused of negligence linked to the rice scheme, which paid farmers above market rates for their crop and became a lightning rod for anger from her political foes.

They allege the scheme drained Thai finances, damaged the country’s rice producing industry and fostered massive corruption -- all to shore up the Shinawatra’s electoral base.

Thaksin is adored by the rural, poor northern portion of the country for his populist policies, but reviled by the Bangkok-based establishment and southern royalists who accuse him of corruption and of undermining the revered king.

Shinawatra-led or linked governments have won every election since 2001.

Anti-government protesters want an appointed “People’s Council” to implement loosely-defined reforms aimed at eradicating Thaksin’s influence on Thai politics.

At least 25 people have been killed and hundreds more wounded in political violence since they flooded Bangkok’s streets and there are fears of wider clashes between pro- and anti-government supporters as the crisis snowballs.

“Red Shirt” chairman Jatuporn Prompan earlier accused the court and NACC of “teamwork” with the anti-government protesters in an attempt to pincer the ruling party – which under Yingluck won a landslide election in 2011.

Warning of an imminent military coup, in a country that has seen 18 successful or attempted coups since 1932, he urged red shirts to join a major rally on Saturday.

The kingdom has been bitterly split since 2006 when an army coup deposed Thaksin.

He now lives overseas to avoid jail for corruption convictions, that he says were politically motivated.

On Wednesday Yingluck became the third premier of a Thaksin-aligned government to be forced from office by the courts.