KUALA LUMPUR, May 9 (Xinhua) -- Ballot counting in the Malaysian election started on Wednesday afternoon as polling stations closed to voters nationwide at 5 p.m. local time (0900 GMT).

The Election Commission (EC) said voter turnout reached 69 percent as of 3 p.m. local time (0700 GMT). EC said earlier it expected voter turnout to reach the same level as last year's 85 percent. But some analysts said voter turnout could be lower due to mid-week voting.

On Wednesday morning, long queues were seen in many polling centers, which led some people to call for voting time extension. But EC chairman Mohd Hashim Abdullah said voting time extension is against election rules.

Due to a re-delineated electoral map before the election, constituencies nationwide tend to have different sizes, with the biggest one packing more than 150,000 voters while some small ones only having 30,000.

Meanwhile, candidates from both the Barisan Nasional coalition and the opposition have complained about receiving non-stop spam calls.

Mohamed Azmin Ali, chief minister of the opposition-held Selangor state, said he received hundreds of continuous calls originating from the United States as well as hundreds of junk emails.

Incumbent Prime Minister Najib Razak ordered an immediately investigation afterwards, saying BN websites also had access problems.

Malaysian police chief Mohamad Fuzi Harun said the attack was seen as an attempt to undermine the peace process of the general election.

He added the police will work with the Communications and Multimedia Commission to conduct a detailed investigation.

The election pits Najib against his former-mentor-turned opponent Mahathir Mohamad, the country's longest-serving prime minister. Results are expected to be unveiled late Wednesday evening.