Polling started at 7 AM amidst tight security arrangements and 38.76 per cent votes were cast till 1 PM, Chief Electoral Officer of UP Umesh Sinha said here.
Maximum 45 per cent votes each were polled in Firozabad and Lalitpur districts.
Among other districts, Etah recorded 43.7 per cent, Etawah 42 per cent, Hamirpur 37 per cent, Mainpuri, Jalaun and Jhansi 39 per cent each and Mahoba 38.
There were reports of voters boycotting the poll process in Etah, Lalitpur, Jalaun and Hamirpur over development issue.
In Kanpur, 32 percent voter turnout was recorded till 1 PM.
There were also reports of minor scuffles between election officials and voters in the industrial city.
The Cantt seat area saw some tension as the local Congress candidate alleged that 75 per cent of voters' names were missing from the voter list despite their having voter-ID cards. Angry voters created a ruckus but heavy police presence prevented the situation from worsening.
Senior police officials said the problem arose due to a minor error in the list which was changed after delimitation and the problem was resolved peacefully with the voters.
Another part of Cantt seat also witnessed similar confusion in the voter list and slogan-shouting among rival party supporters.
In this phase, fate of 829 candidates, including that of Leader of Opposition in the state assembly Shivpal Singh Yadav, BJP leader Uma Bharati and former UP chief minister Kalyan Singh would be decided.
Polling is underway in Firozabad, Kanshiram Nagar, Etah, Mainpuri, Etawah, Auraiya, Ramabainagar, Kanpur, Jalaun, Jhansi, Lalitpur, Hamirpur and Mahoba districts.
The fifth phase would cover assembly seats in backward Bundelkhand region, bastions of SP and former chief minister Kalyan Singh. In this phase, Shivpal Singh Yadav is seeking re-election from Jaswantnagar seat in Etawah district.
Fate of firebrand leader Uma Bharati, who is making her debut in UP electoral politics, would be put to test from Charkhari seat in Mahoba district.
Charisma and political strength of former UP chief minister Kalyan Singh would also be tested in this phase when elections would be held in his stronghold of Etah.