Employment in BMO Financial’s U.S. personal and commercial banking operations, which consists mainly of Harris Bank, fell to 3,965 in the first quarter, down from 4,456 jobs in the fourth quarter.

The Canadian bank released its first-quarter financial results on Tuesday. In an afternoon conference call with Wall Street, an analyst asked BMO about the cutting of 491 jobs, or 11 percent of its personal and commercial banking operations in the United States.

Ellen Costello, Harris chief executive, explained that most of the cuts occurred as Harris integrated Amcore Bank, the publicly-traded Rockford-based lender that failed last April with $3.8 billion in assets.

“When we went through the conversion process, there were about 400 employees that were impacted by that through the fall, and you’re just finally seeing that show up in the first quarter numbers,” Costello said to analysts.

During the call, BMO Chief Executive Bill Downe, whose company is also buying Milwaukee-based Marshall & Ilsley, was asked about BMO’s ability to do another deal.

“We are fully occupied,” he told analysts.

BMO also said that its U.S. loan portfolio is doing reasonably well, but that the commercial real estate industry is still stressed and “will take time for it to recover.”