The media regulator Ofcom has received a total of 2,600 complaints about Sky News's coverage of the general election.

Viewers objected to Adam Boulton's treatment of the Lib Dem leader, Nick Clegg, and his on-screen clash with the former Labour spin doctor Alastair Campbell, and Kay Burley's interview with an electoral reformist.

Boulton, the Sky News political editor, attracted 1,605 complaints. A total of 936 viewers complained about an interview between Boulton and Campbell last Monday, 10 May.

Most of the complainants are understood to have objected to what they viewed as unprofessional behaviour by Boulton, who appeared to lose his temper after Campbell accused him of being "upset that David Cameron is not prime minister".

Ofcom is also assessing 669 complaints that Boulton allegedly "heckled" Clegg about his expenses during the second leaders' debate, which was hosted by Sky News.

The media regulator also received 832 complaints about Burley's interview with electoral reformist David Babbs on Saturday, 8 May.

Burley's interview with Babbs, from the electoral reform campaigning group 38 Degrees, attracted complaints of bias and aggressive behaviour. The interview resulted in Burley being heckled by protesters while she was broadcasting live from College Green in Westminster, with chants of "sack Kay Burley". The incident also sparked a Twitter campaign.

In addition, 163 called Ofcom received 163 joint complaints about the Burley and Boulton interviews.

Ofcom is assessing the complaints to see if there has been a breach of the broadcasting code. It is likely that the number of complaints could still increase, albeit slightly, in next week's complaints bulletin from the regulator.

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