(CNN) -- Police in Montreal were working Wednesday to uncover the motive behind a gunman's midnight attack on the victory speech by Quebec's newly elected premier that left one person dead.
Pauline Marois was speaking to excited supporters near midnight Tuesday when the gunman, dressed in what appeared to be a bathrobe and face mask and armed with two guns, slipped into the Montreal concert hall and opened fire. He then set a small fire at the venue's back door, police said.
Amid the chaos, Marois' security team hustled her off stage. She was not injured, but one person died and another was wounded, according to police.
Minutes later, the 63-year-old returned to thank her supporters and asked the crowd to calmly leave the room.
Montreal police Commander Ian Lafreniere confirmed Marois was the target of the gunman, who was arrested moments after the attack.
Police have not yet released the identity of the dead shooting victim, saying family members may not yet have been notified. The second shooting victim suffered non-life threatening injuries, according to Lafreniere.
As police dragged the man to a cruiser, he shouted in French: "The English are waking up!" CNN affiliate CBC reported.
Marois' party, Parti Quebecois, wants the French-speaking province to secede from Canada and become its own country. Marois and her party defeated the incumbent Liberal party in the elections, making her the province's first female premier.
"As a result of this tragedy, it is all the Quebecois who are grieving today in the face of such a senseless act of violence," Marois said in a statement released by the party.
She said elections, not violence, should guide Quebec's future.
Quebec voters first elected a separatist government in 1976, and since that time the province has quarreled with the English-speaking majority in the rest of Canada over its position in the country.
During her victory speech, Marois told English-speaking Quebec residents that their rights would be respected, CBC reported.
"We share the same history, and I want us to shape together our future," she said in English.
CNN's Paula Newton contributed to this report.