Four men in their 20s were arrested Wednesday for allegedly overturning a small truck during a Halloween event in late October in the busy Shibuya district of Tokyo, police said.

No one was injured in the incident that happened in the early hours of Oct. 28, but it was seen as one of a series of escalating pranks at the popular Shibuya Halloween celebration.

The four — Yuta Kuroki, 27, Takaaki Kawamura, 22, Shota Kojihara, 20, and Rikuo Okubun, 20, — have admitted to the charge of property destruction. They told the police that they did not know each other prior to the incident.

The police believe a total of 15 people, including French and Belgian nationals, were involved in overturning the truck. They said the four arrested were particularly malicious as they were seen standing on the vehicle and damaging it.

The police plan to refer to prosecutors the remaining 11 people.

At around 1 a.m. on Oct. 28, the four men allegedly flipped the truck upside down as crowds in costumes gathered around Shibuya Station in central Tokyo. The driver had left the vehicle to alert police.

The men were identified through security camera footage and images captured by people nearby, the police said.

Concerns are growing over the raucousness of the Halloween street party that is joined by many people clad in costumes and many foreigners. The event is also becoming infamous because of the massive amount of litter that it generates, which needs to be cleaned up.

A total of 19 people were arrested between the night of Oct. 27 and the morning of Nov. 1 over alleged groping and theft offenses, according to police in Shibuya.