end of World War II, when Northern Transylvania became part of Hungary as a result of the Second Vienna Award. On 8 September 1940, upon arrival in Zalău, the Hungarian Army killed 10 people just outside the city; in the following days, the Nușfalău, Treznea, and Ip massacres were perpetrated in nearby villages. Between 1892 and 1896, one of the most famous Hungarian poets Endre Ady attended the Protestant school in Zalău (since 1957, there has been a statue of Endre Ady in front of the school). The poet also published his first poem in the local newspaper "Szilágy" on 22 March 1896. A memorial plaque on the frontage of the building where he lived reminiscents of Ady Endre's time spent there. At the end of the 19th century, Lajos Szikszai donated his private collection to the municipality and the first museum in Zalău was created. An exhibition was also organized in 1926, but the Zalău County Museum was officially inaugurated in 1951. On 9 July 1981, a new section of the Zalău County Museum was inaugurated and was named the "Ioan Sima" Arts Gallery. The "Central Library," owning 7,000 Romanian and Hungarian books, was opened on the 23 August 1950. In 1952 it became "Rayon Library," coordinating all the Zalău Rayon libraries. In 1957 it took the name of Ioniță Scipione Bădescu. It became the "County Library" with the administrative reform of February 1968. As of the end of the 1960s, the city became a regional industrial center for the first time, which was heavily impacted by the Systematization process. Industrial factories like Armătura Zalău, Silcotub Zalău and Anvelope Silvania (recently bought by Michelin) hired thousands of workers, which sparked an increase in population as a result. The population influx gradually led to changes in the ethnic structure with the Romanians being now the majority and the Hungarians reduced to a minority. However, in many of the surrounding communes, the ethnic structure still remained unchanged (for example Vârșolț) are still populated by Hungarians; on the other hand, nearby villages such as Marin have a 100% ethnic Romanian population, basically unchanged for more than a century. In the 1970s with the working-class population expanding, housing estates of high-rise blocks of flats were built in both the centre and the outskirts of the town. In 2007, due to the negligence of the local natural gas distributor, a gas accumulation produced an