A van with the message "Iran Is Great" emblazoned on the side caused London streets to be evacuated Monday. Fearing the vehicle might contain a bomb, police evacuated the streets and neighboring Science Museum. Authorities have since identified the van as part of a secular advocacy group that aims to promote peace and understanding between Iran and Europe.

Authorities evacuated the museum at 9:48 a.m. local time, according to the museum's verified Twitter page. Ambulances, police and firemen soon arrived on the scene and gave the all-clear an hour later. At the center of the perceived bomb threat was the "Iran Is Great" van, parked outside of the Science Museum. Police later discovered that the van was part of a larger mission, founded by an Iranian family that sought to "improve the image of the Iranian people and their country," according to their website. The family had driven across Europe from Iran, passing out pamphlets and giving talks on Iranian culture.

Iran 'tourism' truck sparks Science Museum security alert http://t.co/2gw7SI8FTs pic.twitter.com/sLoxcpb09Q — BBC London Newsroom (@BBCLondonNews) August 4, 2015

The U.K. was part of the agreement signed on July 14 with Iran that attempted to limit Iran's nuclear capacity. One effect of the agreement was to bring Western fears about an aggressive Iran to the forefront of citizens' minds. British Prime Minister David Cameron has been a vocal supporter of the agreement, though not all citizens share his view, with some fearing it could embolden Iran in the future.

Following the deal, Iranian President Hassan Rouhani said he believed one of the greatest effects of the nuclear deal would be to encourage tourism to the country. The "Iran Is Great," program is not connected to the Iranian government, though it has also promoted tourism.

The "Iran Is Great" PR stunt in London seems to have backfired, because of the bomb scare. One of the windows was broken with a rock sometime Monday morning, the group's website reported. An image from the website suggested that one of the family's small children may have been in the vehicle when the window was broken.