A U.S. Border Patrol vehicle drives by the 18-foot (five-metre) high rusty steel barrier along the U.S.-Mexico border at sunset in Brownsville, Texas September 2, 2014. The "Patriots" are a heavily armed group who patrol the U.S. border with Mexico, trying to deter immigrants from crossing the border illegally. The group, who portray themselves as defending the American way, use a strong display of force to intimidate anyone from making the crossing from Mexico into Texas. To critics, they are vigilantes spoiling for a fight. To the immigrants, they are another barrier to entry and to the U.S. Border Patrol, groups like this can either be a nuisance interfering with their operations or an aide in spotting migrants illegally trying to enter the country. Picture taken September 2, 2014. REUTERS/Rick Wilking (UNITED STATES - Tags: POLITICS SOCIETY IMMIGRATION CRIME LAW TRANSPORT) ATTENTION EDITORS: PICTURE 20 OF 20 FOR WIDER IMAGE PACKAGE 'DEFENDING THE AMERICAN WAY'. TO FIND ALL IMAGES SEARCH 'BROWNSVILLE WILKING'

(Reuters) - A tree trimming company has been handed the largest penalty imposed in a United States immigration case, totaling $95 million, after pleading guilty to employing illegal immigrants, the U.S. Attorney’s Office said.

Immigration reform is a major political issue in the U.S., with President Donald Trump saying he will crack down on illegal immigrants and build a wall between the United States and Mexico in order to reduce illegal border crossings.

Asplundh Tree Experts, Co., which trims trees and clears brush for power and gas lines across the country, hired employees who provided fake identification documents from 2010 to 2014, the U.S. Attorney’s Office in Philadelphia said.

The prosecutor said on Thursday that Asplundh’s management were “willfully blind”, while supervisors and general foremen hired illegal immigrants through word of mouth referrals.

“This decentralized model tacitly perpetuated fraudulent hiring practices that, in turn, maximized productivity and profit,” it said.

The company’s chairman and CEO Scott Asplundh said in a statement that it has taken steps to improve its hiring practices, including reviewing the identification of all employees.

“We accept responsibility for the charges as outlined, and we apologize to our customers, associates and all other stakeholders for what has occurred,” he said.