An agency of the Department of Homeland Security is in danger of violating federal laws against overspending congressionally approved budgets, in part because of flawed financial accounting systems it inherited from the old Immigration and Naturalization Service, a Democratic member of Congress said yesterday.

"I am deeply concerned about reports my staff are receiving from various personnel" at the Bureau of Immigration and Customs Enforcement (ICE), Rep. Jim Turner (Tex.), the senior Democrat on the House Select Committee on Homeland Security, wrote to the department's inspector general. "These conversations revealed a severe lack of confidence" that the bureau's financial system is yielding accurate, timely information, he wrote.

ICE funds often are hastily moved among the bureau and its sister agencies to cover budget shortages, Turner said. ICE pilots don't know whether they can acquire fuel or spare parts, and some vendors are not being paid promptly because of glitches in the financial system, he said.

Homeland Security spokesmen said the bureau's financial systems are working adequately and denied that the agency might find itself in violation of laws against agency overspending.

"The budget is tight, but we're managing the budget we're given," department spokesman Dennis Murphy said. "People are meeting daily to work these things out."

In March, the Border and Transportation Security directorate -- ICE's parent organization within Homeland Security -- announced a temporary hiring freeze because of a budget crisis. The cause was lower-than-expected employee attrition, and the fact that combining the agencies' different financial systems made it difficult to track funds, officials said.

The 20,000-employee ICE -- which investigates the smuggling of arms, cash and illegal immigrants -- was created by the blending of parts of the former INS, the former Customs Service and the Agriculture Department's plant inspectors.

Many agents from the old Customs Service, which was a relatively high-performing agency with an esprit de corps, have expressed deep frustration at being forced to merge with the old INS, widely viewed as dysfunctional. Some of them call ICE "INS-occupied territory." One of their complaints is that ICE still uses some of INS's balky accounting and record-keeping systems.

Yesterday, Turner took up the cause of these agents. In his letter to Homeland Security's inspector general, Clark Kent Ervin, Turner asked for an investigation of ICE's financial practices.

"Problems with [ICE] financial systems have crippled the ability of managers and staff to fulfill their responsibilities," Turner wrote. "It is puzzling to me that the department would choose to stay with a [financial] system so widely recognized as inherently flawed."

"I understand that deficiencies in the ICE Federal Financial Management System are so severe that they place the bureau at risk of violating the Anti-Deficiency Act," which bars spending money Congress has not appropriated, he wrote. Violators of the act can face demotion or criminal penalties, he pointed out.

Former customs agents who now work at ICE welcomed Turner's letter. "INS was abolished by Congress, but its broken-down practices live on here at ICE," said one, who spoke on the condition of anonymity because of the issue's sensitivity.

Murphy said contending with the different financial systems used by ICE and its sister agencies is extremely difficult for the department.

"I won't sugarcoat the budget situation," Murphy said. "It is not a walk in the park. It's a multi-year effort to get this all to work smoothly. It's not smooth yet."

Rep. Jim Turner (D-Tex.) criticized the Bureau of Immigration and Customs Enforcement.