Tragedy has struck again within the United States’ school system, after a murder-suicide shooting occurred at UCLA.

Los Angeles police have stated “two people died in a murder-suicide in an engineering building at UCLA on Wednesday”.

One of the individuals involved was William S. Klug, 39, who was an associate professor of Mechanical and Aerospace Engineering.

The attack precedes the United State’s second annual National Gun Violence Awareness Day.

The day calls for American citizens to raise awareness about gun violence and to wear orange – a colour that symbolises the value of human life as hunters often wear orange in the woods to protect themselves and others.

The campaign was first launched after Chicago citizen Hadiya Pendleton, 15, lost her life to gun violence in 2013.

Since the tragic event, the campaign has turned into a nationwide movement to honour all lives which have been cut short by gun violence and lack of United States’ gun regulation laws.

After the Sandy Hook Elementary School massacre in Connecticut in 2012, the activism group Every Town For Gun Safety was established, recording school shootings across the United States of America.

Since 2013, there have been 185 school shootings in the United States, with 25 of these events being recorded in 2016. These singular events also include incidences where a gun has been shot on school grounds with nobody being injured or killed.

National Gun Violence Awareness Day will be held on June 2nd (June 3rd AEST) and 2016 is estimated to be the biggest year yet for the campaign.

Iconic landmarks across the United States, such as the Empire State Building, are to be illuminated in the shade of orange to promote the activism campaign and to call for gun restrictions.

Participants are encouraged to ‘be creative’ and ‘be loud’, sharing their photos and participation across social media platforms with the hashtag #wearorange.