Ljunggren was a member of the Rebels Motorcycle Club, which was formed in Helsingborg in 1981. The Rebels were affiliated with the Hells Angels chapter across the Øresund strait in Helsingør and, through this association, Ljunggren became acquainted with Hells Angels member Jan "Face" Krogh Jensen. In 1984, Ljunggren founded the White Trash MC with Jensen and another Danish biker who had moved to Helsingborg, with the intention of eventually forming a Hells Angels chapter in Sweden. The White Trash became closely associated with the Black Sheep MC, a Hells Angels prospect club in Roskilde which later became Hells Angels South. Two Black Sheep members, including Jan "Clark" Jensen, took refuge with the White Trash in Helsingborg following the Copenhagen Biker War. The White Trash also had good relations with Hells Angels in Helsingør and its then president Michael Lerche Olsen. The Helsingør Hells Angels chapter closed in the spring of 1986 following an internal feud, however. The same year, police raided the White Trash's clubhouse while searching for Jan "Clark" Jensen and discovered weapons and stolen goods, which resulted in Ljunggren being sentenced to prison. The police operation and Ljunggren's imprisonment caused the White Trash to disband, and Ljunggren applied to return to the Rebels. He withdrew from the biker club scene following the birth of his second son in 1989 and, in 1991, spent time riding through the United States with a friend Kalle, another former Rebels member. Upon his return to Sweden, he joined the Morbids MC, which had been formed in Helsingborg earlier that year. In 1993, a fight took place between the Morbids and the Rebels in Stockholm which left several Morbids members beaten. Some time later, the Hells Angels in Malmö offered a path to membership for the Rebels and Morbids on the condition was that the clubs were merged and that Michael Ljunggren and his friend Kalle were not members. The Morbids – a club with only six members – rejected the invitation and, requiring support in its feud with the Hells Angels, instead began an affiliation with the Undertakers MC in Zealand, who had contacts with the first Bandidos chapter in Europe, located in Marseille. The Undertakers were patched over by the Bandidos in December 1993 and the Morbids followed suit in January 1994. Ljunggren became the Bandidos Sweden national president. Upon its foundation, the Bandidos chapter in Helsingborg was attacked by the Hells Angels, beginning the Nordic Biker War.
Murder
On 17 July 1995, Ljunggren was returning from a visit to the Finnish branch of the Undertakers in Helsinki – which would become a Bandidos probationary chapter the following month before being patched over in October 1996 – with Jan "Clark" Jensen, who joined the Bandidos earlier that year after leaving the Hells Angels. The pair boarded a ferry to Stockholm then rode their Harley-Davidson motorcycles in the direction of Helsingborg. Jensen's motorcycle broke down in Ljungby, however, and Ljunggren continued the journey alone. He was shot while riding his motorcycle on the E4 motorway, south of Markaryd, Småland. He then fell from his bike and was run over by a car. An ambulance took him to a nearby hospital, with doctors initially thinking a simple road accident had occurred. Only at the hospital did it become clear that he had been shot several times by a rifle. He was wearing a flak vest, but one of the shots penetrated the armour, striking him in the back and killing him. There are various theories as to how Ljunggren was shot. One presumption is that he was shot by a sniper; this theory is supported by the testimony of two witnesses, a Danish couple. Another is that he was shot from a car driving behind him, which is supported by the police technical examination of the bullets' trajectory. The murder has gone unsolved and has become a cold case, although police believe the Hells Angels were involved. Information obtained by police from a mobile phone network indicates that Hells Angels members' phones were used and moved along Ljunggren's route from when he stepped ashore in Stockholm. Suspects include a Hells Angels prospect club from Helsinki, Choppers MC from Stockholm or another Hells Angels prospect club from Helsingborg.
