The Iceland incident was humanity's first encounter with extraterrestrial life, it unfortunately proved that Aliens had hostile intentions towards humanity. However the event led to the creation of the Xenonauts.
On April 23, 1958 NATO and US radar picked up an unidentified flying object flying near US airspace, initially it was thought that it was a Nuclear Missile, however the fact that it was only a single contact as well as its sudden change of trajectory quickly eliminated that theory. Soon every fighter on the Atlantic coast was launched to intercept the UFO, the Soviets also began launching their own fighters in Europe, thinking that a NATO invasion was occurring, however talks soon began between NATO and the USSR. A squadron of F-8 fighters intercepted the UFO, they attempted to communicate with the craft. However as they approached the craft the fighters were fired upon. Of the six fighters in that squadron only a single heavily damaged fighter returned to base.
Soon NATO responded by firing six Nuclear Missiles at the UFO in a spread pattern, so that when the missiles detonated it would envelop and destroy the UFO, like a shotgun. It was somewhat successful as the craft was hit and crashed into Southern Iceland.
NATO and Soviet troops started to land near the Crash site, with a command post being set up. The plan was for the combined forces to encircle the UFO and to slowly close in on it. The attack force consisted of troops and tank support.
Eventually the order came to advance on the wreckage. When the troops closed to about one kilometre they came under heavy fire from the surviving Alien crew, the human forces suffered heavy casualties as even tanks were sliced apart with ease.
However the human forces pressed forward, and soon the Aliens were evidently losing the battle, several hours after the battle started and as the human forces were about half a kilometre from the crash the Aliens detonated their power source, the resulting explosion completely wiped out the entire advance human forces and the UFO, with the only survivors being the Officers at the command post and wounded pulled back from the fighting.
The event was covered up as a attempted Soviet invasion of Iceland, a joint Soviet-NATO force was stationed at the crash area and scientists began studying what had survived the explosion, which was basically nothing.
However. this incident caused NATO and the USSR to form the Xenonauts, an international organization designed to combat any future Alien threats, armed with the best humanity had to offer.