OTTAWA -- Firebrand New Democrat MP Pat Martin is apologizing for another abusive Twitter outburst -- and swearing off the microblogging service for good.

Martin's Twitter account was abruptly shut down Thursday after an abusive series of tweets prompted, apparently, by the Conservative government's failure to invite him to an announcement in his Winnipeg Centre riding.

"I apologize for my regrettable and inappropriate language," Martin tweeted as word of the angry tirade continued to circulate online.

"It seems some people shouldn't tweet so with this, I sign off."

Indeed, NDP spokesman Karl Belanger quickly confirmed Martin's decision.

"These comments were simply inappropriate and unacceptable," Belanger said in a statement. "Mr. Martin agrees and we understand that he has decided to stop using his Twitter account."

Following his last tweet, clicking on Martin's Twitter name -- @PatMartinMP -- yielded only an "internal server error."

Wednesday night's tweets were laced with abusive language and included some particularly scathing and personal insults aimed at Public Safety Minister Vic Toews and the Conservative party.

Among other things, Martin described the Conservatives as "truly bad people" who won last year's federal election using "American-style dirty tricks."

It wasn't the first time Martin had raised eyebrows on Parliament Hill and across Canada with Twitter-based vitriol.

In November 2011, he went on a similar, profanity-laced tirade when the government used procedural tools to shut down debate on a budget bill.