Thai protesters who have massed on Bangkok’s streets for six months said on Thursday they would appoint a new government, following the removal of premier Yingluck Shinawatra by a court. The announcement comes as the ailing ruling party seeks to bolster its authority after Yingluck’s dismissal. Observers warned the move would be likely to enrage pro-government supporters, risking further violence as the country lurches deeper into a political crisis. An indication of future conflict came when a grenade was thrown at the home of a court judge on Wednesday night, police said on Thursday. Police Colonel Kamthorn Auicharoen said that there were no casualties and that the attackers were trying to instigate a situation to further deepen the political conflict. The headquarters of Thailand’s major commercial bank and a scientific research facility were also damaged by similar grenades overnight. “Tomorrow [Friday] we will take steps towards appointing a new government,” protest spokesman Akanat Promphan told reporters, adding the new prime minister named after the court ruling lacked legitimacy. “After the Constitutional Court’s decision yesterday we decided to move up our schedule ... the government has lost all legitimacy and any claim it has to govern the country.” It was not immediately clear what legal basis their vow draws on, but the Thai constitution has an article that may enable the appointment of a new executive body by the Senate. “The government has lost all legitimacy and any claim it has to govern the country.” Akanat Promphan Anti-government protest leaders have vowed a “final fight” on Friday, without giving details of their plans. Their pledge comes a day after the Constitutional Court removed Yingluck from office for abusing her power in the 2011 transfer of a security official. The court, which removed two previous pro-Thaksin prime ministers in 2008, ruled that Yingluck and nine of her cabinet ministers had abused their power in 2011 over the appointment of a security agency chief. The court left the Shinawatras’ ruling party in charge of a caretaker administration intent on organising a July 20 general election, which Yingluck and the party would be likely to win. Yingluck said on Wednesday she had yet to decide on her future, but a return to power via the ballot box could be blocked if the NACC case also goes against her. Had Yingluck been prime minister, the commission could have forwarded the case to the upper house Senate to consider impeachment and a political ban, the official said. Now it might recommend criminal proceedings which could also result in a ban. The ruling Puea Thai party accused the court of a “conspiracy” against the administration, many of whose ministers are loyal to Thaksin Shinawatra – Yingluck’s billionaire brother and a former prime minister ousted in a military coup. 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. 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. Puea Thai swiftly appointed a deputy premier – Niwattumrong Boonsongpaisan – as Yingluck’s replacement. He is a staunch Thaskin loyalist. The National Anti-Corruption Commission (NACC) was due to meet on Thursday to consider a separate case of negligence against Yingluck over a rice subsidy scheme that incurred billions of dollars in losses. The ruling could lead to a five-year ban from politics. "Today, the NACC will decide whether former premier Yingluck is guilty or not in the rice case and how to proceed with the case," said an official at the National Anti-Corruption Commission, who declined to be identified as she was not authorised to speak to the media. Observers say the anti-government movement is banking on legal rulings to chisel away at the new administration. They have been camped on Bangkok’s streets for six months in a bid to topple Yingluck and rid the country of the influence of her brother. 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 intensifies. "This is the first time both sides will protest near each other and each have hardcore elements which is extremely worrying," said political analyst Kan Yuenyong at the Siam Intelligence Unit think-tank. Grenade attacks and sporadic gun battles have become increasingly frequent as the crisis has dragged on. There were four grenade or small bomb blasts in Bangkok on Wednesday, night including one at the home of a Constitutional Court judge. No injuries were reported, police said. The military, which has a long history of intervening in politics, has said it will try to stay out this time, but would step in if violence worsens. Army spokesman Winthai Suvaree said there were no plans to increase troop numbers in Bangkok. More turmoil would make matters worse for Southeast Asia’s second-largest economy, already teetering on the brink of recession amid weak exports, a year-long slump in industrial output and a drop in tourism, and presided over by a caretaker government with curtailed powers. 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. Shinawatra-led or linked governments have won every election since 2001. The anti-government protesters say Thaksin buys elections and, to end his hold over politics, they say reform of the electoral system has to be implemented before new polls. On Wednesday Yingluck became the third premier of a Thaksin-aligned government to be forced from office by the courts, who critics say support the Thai elite. Additional reporting by Reuters