Tutor Perini Corp. late Thursday reported third quarter profits that were below Wall Street expectations as its engineering and construction business was hurt by the slow economy.

The company also announced a $9.75 million settlement with the U.S. Department of Justice related to a minority-owned business subcontracting investigation.

After the markets closed, the company, which moved its headquarters from Boston to Sylmar last month, reported net income was $26.7 million (54 cents a share), compared with $34.1 million ($1.01) a year ago. Revenue fell 17 percent to $1.17 billion.

After one-time items, per-share earnings were 59 cents. Analysts surveyed by Thomson Reuters on average were expecting adjusted earnings of 61 cents per share on revenue of $1.29 billion.

The company said the results were affected by completion of large gaming and hospitality work and a reduced level of new nonresidential building work. Based on recent winning bids, the company expects that about 40 percent of operating income in 2010 will come from the civil engineering group, compared with 20 percent estimated in 2009.

“The company has demonstrated its competitive strength in the civil infrastructure markets as evidenced by the recent contract wins in New York and California,” Chief Executive Ronald Tutor said in a statement. “Our goal to be a more diversified general contractor will be achieved next year with our civil and management services groups contributing over half of our operating profits at significantly higher margins than what we are able to achieve in our building business.”

Tutor Perini said separately that the Justice Department settlement agreement resolves all outstanding issues related to a federal investigation into subcontracts with certain minority-owned and disadvantaged-owned enterprises on construction projects in New York City between 1998 and 2003. No criminal charges will be brought against the company.

The $9.75 million settlement was fully expensed in prior years and will have no material impact on Tutor Perini’s 2009 financial results, the company said.

Before the announcements, shares closed up 40 cents, or 2 percent, to $18.69 on New York Stock Exchange, and rose another 2 percent in after-hours trading.