TORONTO - Large-scale building projects across Ontario moved slower Wednesday as almost 3,000 crane and other heavy-equipment operators walked off the job to push for more money and other contract demands.

Within hours of the strike, projects as diverse as construction at a hospital in North Bay and a Toyota plant in Woodstock were affected, with predictions of more to come.

The striking members of the International Union of Operating Engineers Local 793 operate construction cranes, bulldozers and similar equipment, or work as surveyors.

"We never like to see this kind of work stoppage,'' said Michael Smith, spokesman for EllisDon Corp., one of the employers involved in negotiations with the union. "It certainly hurts our progress.''

Smith was unable to say how many work sites had been affected, given how early it was in the walkout.

"Some sites have tower cranes, so they're quite susceptible to operators going out,'' Smith said.

The strike hit major industrial, commercial and institutional construction projects across the province. The union's business manager, Michael Gallagher, said the key issue in the dispute is wages.