A concert by the K-pop supergroup BTS has attracted tens of thousands of fans to South Korea's second largest city of Busan.

The group staged the free show from about 6 p.m. on Saturday to support the city's bid to host the 2030 World Expo.

Many people wearing purple, the boy band's symbol color, formed long lines at the venue before the gates opened.

The group's management office said before the event that it expected an audience of about 50,000 people. Fans were asked to wear masks as a precaution against the coronavirus.

The performance was also broadcast live at public viewing sites. The landmark Busan Tower and other public facilities were lit up in purple to add to the sense of excitement.

The concert took place after the South Korean government lifted quarantine measures for entrants earlier this month. The number of foreign tourists has been gradually increasing.