Subscribe | UPI Odd Newsletter Subscribe WASHINGTON, May 13 (UPI) -- North Korea's military fired a laser in March at two U.S. Army helicopters patrolling the demilitarized zone, The Washington Times said Tuesday. "These are blinding laser weapons," one official told the Times. Advertisement The U.S. helicopters were illuminated by a weapon that had the characteristics of a Chinese laser gun, an indication North Korea has deployed a new and potentially lethal weapon. The laser illumination occurred around the time that four North Korean jets intercepted a U.S. spy plane and attempted to force it to land in North Korea, according to the report. Army Col. Samuel T. Taylor, a spokesman for U.S. Forces Korea, said the helicopter incident happened during a routine training mission. "Two USFK pilots were alerted by onboard laser-detecting equipment that laser systems may have illuminated their aircraft," Col. Taylor said in a statement. "Neither pilot was injured, and no equipment was damaged." Taylor said laser detections occur occasionally along the DMZ. But U.S. intelligence officials told the Times that an internal analysis of the incident suggests North Korea has acquired Chinese-made ZM-87 anti-personnel lasers. The ZM-87 is the only laser device designed for use against troops, and can cause injuries to human eyes at a range of just under two miles, according to military specialists. Advertisement The Apache pilots and crew were not wearing laser eye protection when the incident occurred. "Neither pilot was injured, and no equipment was damaged," said Taylor.