Small groups of protesters demonstrated outside the US embassy last weekend when Philip Goldberg, newly appointed as US ambassador to South Korea, arrived in the country, accusing the US of “homosexual cultural imperialism”.

Seoul’s presidential security service said it would strengthen security measures for President Yoon Suk-yeol, and the National Police Agency has ordered regional branches to step up monitoring to guard key figures.

“We are reviewing our security system for the president following the Abe shooting and will take necessary measures to strengthen our security posture,” an official at the presidential agency said.

Abe, Japan’s longest-serving prime minister, was gunned down on Friday during a campaign speech in the western city of Nara in a killing that stunned a country where political violence and gun crime are extremely rare.

Police are also gearing up for the Seoul Queer Culture Festival on Saturday. As well as US ambassador Goldberg, other envoys to the country are expected to attend.

“We are planning to tighten security as there are a number of risk factors with opposition groups also set to hold a rally at the same time,” a police officer said.

Homosexuality is not illegal in South Korea and there is growing public acceptance of LGBTQ relations. But rights activists say many LGBTQ people still suffer hate crimes and face discrimination, including job loss and hate speech.

Security for US ambassadors in Seoul has been a source of controversy.

In 2015, a South Korean man slashed then US ambassador to South Korea Mark Lippert in the face with a fruit knife at a forum, leaving a deep gash to his face that required 80 stitches.

And in 2019 as many as 20 protesters climbed the wall into the US ambassador’s residential compound, the second illegal entry there in just over a year. Police boosted security at the site after the US state department publicly complained.