Reports claim Facebook is on the brink of introducing its most intrusive ad unit yet – auto play video ads in users’ news feeds.

Several TV advertising executives in the US confirmed to Ad Age the social network will make a play for TV ad dollars early next year by introducing video ads to its website and mobile apps.

The ads, which are slated for launch in April, are expected to be 15-seconds long and grab users’ attention by expanding into the left and right columns – the rails – of the desktop website, with plans to ensure they stand out on mobile too.

“The assumption is that these would be widespread campaigns,” one of the execs told Ad Age. “They are looking to grab big chunks of money… millions of dollars.”

Concerns have already been voiced about the impact of increasingly intrusive ads on Facebook users, with its members generally unwelcoming of commercial messages invading their social conversations.

Auto-play video ads in particular have the potential to cause backlash among Facebook users, a point several of the executives told Ad Age they had serious concerns about.

“There could be serious outrage,” one of Ad Age‘s sources said.

In addition, advertisers will be able to show the same video ad to a Facebook user up to three times a day across various devices, according to details leaked by those privy to Facebook’s briefing. Videos from brands that users haven’t ‘liked’ could also wind up in news feeds.

The execs expressed concerns that Facebook members will quickly become tired of ads from advertisers with which they or their friends have no relationship, even if advertisers tailor the ads based on information in a person’s profile.

Facebook declined to comment when contacted by Ad Age, according to the report.