Islamabad, Jul 25 (IANS): Voters in large numbers on Wednesday morning started flocking outside polling stations across the country to cast their votes in Pakistan's 11th general election.

The first vote was cast in Khyber Pakhtunkhwa's Charsadda, according to Dawn news website.

While polling stations officially opened for voting at 8 a.m., enthusiastic citizens queued up outside their respective stations as early as 7 a.m, the website said. Polling stations will remain open for voting till 6 p.m.

As many as 12,570 candidates are contesting for a total of 849 seats of national and provincial assemblies in the general election.

The battle is set to come down to three parties: Shahbaz Sharif's Pakistan Muslim League-Nawaz (PML-N), Bilawal Bhutto-Zardari's Pakistan Peoples Party (PPP) and Imran Khan's Pakistan Tehreek-i-Insaf (PTI).

In an effort to increase voter participation the Election Commission of Pakistan has declared a public holiday on Wednesday.

Over four lakh security personnel have been deployed at polling stations across the country to maintain law and order and take action against harassment, after the nation witnessed one of the bloodiest campaigning on July 13.

According to a poll official, 5,878 polling stations have been declared "highly sensitive" -- official euphemism to mean they are prone to violence -- in Sindh; 5,487 in Punjab and Islamabad; 3,874 in Khyber Pakhtunkhwa and FATA and 1,768 in Balochistan.

According to the reports, women voters were being denied the right to vote in PK-65 constituency of Nowshehra in Khyber Pakhtunkhwa Province.

Geo TV said a suspicious person was detained when he tried to enter Karachi's Lyari Bihar Colony polling station in NA-246, claiming to be a police officer.

"The suspicious person has been taken to Chakewara Police Station," a police officer said, adding that the polling process was halted for about 20 minutes.