NDP Leader Tom Mulcair had some choice words for Bob Rae during Monday's Munk leadership debate, but the former NDP premier of Ontario was quick to strike back via Twitter.

While explaining his party's track record on balanced budgets, Mulcair noted one exception, Rae's years as premier during the early 1990's.

"But it turned out he was a Liberal," Mulcair quipped.

Rae served as NDP premier of Ontario from 1990 to 1995, a period that saw net provincial debt more than double, according to RBC. Rae later jumped to federal politics as a Liberal, eventually serving as interim leader from 2011 through 2013.

In a burst of return fire on Twitter, Rae got in a few jabs of his own.

He defended his record as premier.

Very tired line from Mulcair - "sort of like being attacked by a dead sheep"- proud to have led a govt that re-built Ontario at a tough time —@BobRae48

Praised Pierre Trudeau (who Mulcair attacked at the debate)

I didn't always agree with Pierre Trudeau but he was a great man. I can't say the same about Tom Mulcair <a href="https://twitter.com/hashtag/cdnpoli?src=hash">#cdnpoli</a> —@BobRae48

And pointed out that Mulcair was once a Liberal himself.

Mulcair's entire "record" on the environment was when he was a Liberal. So I guess it didn't count. <a href="https://twitter.com/hashtag/cdnpoli?src=hash">#cdnpoli</a>. —@BobRae48

He ended with this zinger.

Nastiness is one thing, recycled nastiness is worse. <a href="https://twitter.com/hashtag/cdnpoli?src=hash">#cdnpoli</a> —@BobRae48

In a story that mirrors that of Rae, Mulcair served as a Liberal MNA in Quebec's National Assembly from 1994 to 2007, before moving to federal politics as a New Democrat.