Alward leader took an unprompted shot at Trudeau's position at the end of a news conference about a labour mobility agreement with British Columbia.
"Justin Trudeau is 50 years late," the Progressive Conservative leader said in Charlottetown.
"The reality is the scientific work has been taking place over the last 50 years. Fracking has been taking place safely across our country for the last 50 years."
Alward, who is trying to get re-elected in his province's Sept. 22 election, made his comments after Trudeau waded into the controversial issue of shale gas development while he campaigned alongside provincial Liberal Leader Brian Gallant last weekend.
While at a rally Saturday in Moncton, N.B., Trudeau said he agreed with Gallant's position that more science is needed before the shale gas industry is allowed to expand.
The question over whether to develop New Brunswick's deposits of shale gas has dominated the early days of the election campaign.
Alward launched his re-election bid a week ago in front of a field of natural gas wells, promoting the merits of an industry he says can reverse New Brunswick's economic woes.
The issue has been contentious. Nearly a year ago, protests over shale gas development spiralled into violence when the RCMP enforced an injunction to end a blockade outside an energy company's storage compound in Rexton, N.B. Police cars were torched and dozens were arrested.
At dissolution, the Tories had 41 seats, the Liberals 13 and there was one Independent.
This election is being fought on a new electoral map that cuts the number of seats to 49 from 55.
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