DHAKA (AFP) - Emergency authorities in Bangladesh on Thursday released former prime minister Khaleda Zia as part of efforts to restore democracy in the South Asian country by the end of the year. Zia, 63, walked out of jail after spending just over a year locked up over alleged corruption dating back to her two stints as premier from 1991-1996 and 2001-2006, her lawyer said. Her release on bail - with graft charges still in place - comes as the army-backed govt seeks to relinquish power and hold nationwide elections in late December. The participation of Zia's Bangladesh Nationalist Party is seen as crucial for the success of the polls, which will bring an end to nearly two years of emergency rule. Zia left the prison, where she had been held since September 3 last year, just before noon. She visited the grave of her husband, slain president Ziaur Rahman, before heading to the hospital where her ailing son Tareque Rahman - also accused of graft and bailed last week - is being treated. Thousands of supporters gathered outside the prison, the cemetery and hospital to greet Zia, who was dressed in a white sari. "I am not saying anything now," Zia said from her vehicle en route to the hospital. "I will say everything later," she told reporters. Her son Rahman - who alleges he was tortured in custody - has been issued a British visa and could fly to London for treatment for a spinal injury as early as Thursday evening, another lawyer Nadir Uddin Amir said. The government also wants Zia to travel abroad for medical treatment for her arthritic knee, but she does not want to leave. She face charges in four separate cases of corruption and misuse of power, including in the awarding of state contracts. No trial dates have been set. Although the army-backed government wants Bangladesh's major parties to take part in the polls, observers say it clearly wants to prevent the two-time premier from returning to office.