Published: 2021-07-25 23:30:36 BdST
Supporters of the ruling Pakistan Tehrik-e-Insaf (PTI) party of Prime Minister Imran Khan and opposition Pakistan People's Party (PPP) clashed in one constituency, leading to the deaths, police officer Mohammad Shabir told Reuters by phone.
It was not immediately clear which party they backed.
Four soldiers in a rapid response team involved in securing the poll also died when their vehicle plunged into a ravine in the mountainous area, the army said. Three more were injured.
The violence mars the latest election test for Khan, who has faced growing criticism since his 2018 election win over his handling of the economy and competence to deliver on his election promises.
Typically, the Kashmir vote has been won by the country's ruling party. Analysts said this race was tighter than usual.
More than 700 candidates from Pakistan's three major political parties, which also include the Pakistan Muslim League (PML-N), alongside two local groups are running for 45 seats, a local election commission official Nasir Jan said.
About 3.2 million people are registered to vote, he said.
Unofficial results are likely to be announced overnight.