Canadian police have charged a man with sending explosive devices to law firms and other businesses in the city of Winnipeg days after a woman was seriously injured in an explosion.

Guido Amsel, 49, has been charged with two counts of attempted murder, one count of aggravated assault and a number of offences related to possessing explosives. Police said Monday that Amsel targeted law firms that represented him or his ex-wife in the past.

A bomb exploded last Friday at the offices of a law firm in Winnipeg in central Canada, severely injuring a woman who worked there.

Another bomb was found Saturday at a small business in another part of the city. Another explosive device was detonated by police Sunday at another law firm.