NAYPYITAW, Myanmar (AP) ' Security forces seized control of the headquarters of Myanmar's ruling party as internal rifts intensified ahead of general elections. The party chairman, who has steadily lost support of the powerful military, was holed up in his home after being removed from his post during the aggressive midnight reshuffle.Tensions have been building for months between President Thein Sein and Shwe Mann, who up until Wednesday led the Union Solidarity and Development Party.The men, both retired army generals, each have expressed interest in leading the country.An internal meeting was held Wednesday at the ruling party headquarters in the capital, Naypyitaw, to announced candidates for the upcoming polls.Members also were told Shwe Mann had been dismissed as party chair, sparking outcry by some. It was not clear if he will stay on as the influential speaker of parliament."I heard something is going on with the changing of party leaders or high-ranking offices," Minister of Information Ye Htut said on his Facebook page, adding there was little more he could say as it was an internal party matter.Myanmar only recently began transitioning from a half-century of dictatorial rule to democracy.The Nov. 8 general election will be the first since a nominally civilian government was installed in 2011. But with the military still firmly in control of the process, there has been widespread speculation as to whether it will be free and fair. Opposition leader Aung San Suu Kyi, who enjoys huge public support, is barred from running for president but is seeking re-election to Parliament.There was no public explanation Thursday for Shwe Mann's ouster. He was temporarily replaced as party chair by his deputy, Htay Oo, the party said on its website.Witnesses said trucks started arriving at the USDP headquarters on Wednesday night. Soldiers and police were seen entering the building and some party members were prevented from leaving, though by Thursday afternoon only a few police were deployed at the gate of sprawling compound.Thein Sein was handpicked by former dictator Than Shwe and has retained the support of the armed forces despite implementing some reforms, including the freeing up of the media and the release of political prisoners ' though there have been hundreds of new arrests under his watch.He was holding an emergency meeting with cabinet members Thursday.Shwe Mann's relationship with the military, meanwhile, has deteriorated steadily in the last year.Seen as a reformist ' and an ally of Suu Kyi ' he was accused by military MPs recently of creating "misunderstandings" between the public and the armed forces.That followed his support for a call in parliament to amend Article 436 of the Constitution, which gives the military the power to veto all amendments.A witness said Shwe Mann's home security official was seen being questioned by the chief of police. Not seen publically since the news, he was believed to be inside."My father is right now at his home in Naypyitaw with the security guards," said Toe Naing Mann, Shwe Mann's son. "I don't know whether he is allowed to go out or now."___Associated Press reporters Aye Aye Win and Esther Htusan contributed to this report from Yangon.Join the conversation about this story Click here to read full news..