ISLAMABAD:- At least 31 people were killed, including 28 in a suicide blast outside a polling station in Pakistaninfo-icon's Quetta city and 36 others injured as several incidents of violence were reported as the country went to polls.

In Pakistan's restive Balochistaninfo-icon province, a suicide blast targeting a police van killed at least 28 people, including five policemen, and nearly 30 other were injured in a blast near Quetta's Eastern Bypass, The Express Tribune reported.

Quetta is the provincial capital of Balochistan province.

The blast took place near Quetta's Eastern Bypass when the police van was targeted in the attack. The attack was part of a larger pattern of attacks targeting security forces vehicles and not targeting the electoral process, the report said.

The suicide bomber wanted to enter the polling station, a police spokesperson was quoted as saying by the GEO News.

DIG Abdul Razzak Cheema's convoy was attacked. He is reported to be safe, according to sources.

In Khyber-Pakhtunkhwa's Swabi district, supporters of two rival parties exchanged fire outside a polling station, killing a worker of former cricketer Imran Khaninfo-icon's Pakistan Tehreek-e-Insaf (PTI) and injuring two others, police said.

The PTI worker was killed as party activists clashed with Awami National Party (ANP) workers outside a polling station for NA- 19 (Swabi II) and PK-47 (Swabi V) in Nawan Kali area.

Another person was killed in firing outside a Mirpurkhas polling station in NA-219 Dighri area, the report said.

In a separate incident, four people were injured in a cracker blast outside a political camp in Larkana.

Voting has been halted across Larkana NA-200/PS-11 post the explosion.

According to the Election Commission of Pakistan (ECP), 3,459 candidates are contesting for 272 general seats of the National Assembly, while 8,396 candidates are running for 577 general seats of the four provincial assemblies - Punjab, Sindh, Balochistan and Khyber-Pakhtunkhwa.

There are 105.96 million registered voters in the country. The voting started at 8 AM local time on more than 85,000 polling stations. The counting of votes will be done on the spot soon after polling is concluded and results will be announced within 24 hours.

For a smooth polling process, the Election Commission of Pakistan (ECP) has deployed around 1.6 staff at polling stations across the country.

About 449,465 policemen and over 370,000 military personnel have been deployed for security.

In a special message yesterday, Chief Election Commissioner Justice (retd) Sardar Raza Khan urged voters to fulfil their national duty of casting the ballot.

A public holiday has been declared across the country on Wednesday in order to facilitate the voting process.

Pakistan's National Assembly comprises a total of 342 members, of which 272 will be directly elected today whereas the rest -- 60 seats reserved for women and 10 for religious minorities -- are selected later through proportional representation among parties with more than five per cent of the vote.

A party can only form the government if it manages to clinch 172 seats in total.