Election officials in Bangladesh say former prime minister Sheikh Hasina has taken an early lead in unofficial election results.
Her alliance has reportedly won 50 out of 65 seats so far in the 300-seat parliament and is ahead of an alliance led by Begum Khaleda Zia, another former prime minister, in many other constituencies.
The two leaders previously alternated in power for 15 years until 2006.
The election on Monday is to return Bangladesh to democracy after two years of emergency rule.
A military-backed interim government took over in January 2007, following widespread street violence between supporters of rival parties, and cancelled elections due that month.
The government has deployed 50,000 troops, 75,000 police and 6,000 members of an elite battalion along with other auxiliary forces for security.
About 200,000 local and 2,000 foreign monitors were at the election centres to check procedures.