Photo/IllutrationStudents practice a six-layer pyramid as their teachers watch over them at a junior high school in Kumamoto in 2017. (Asahi Shimbun file photo)

KOBE--Fun to achieve and impressive to see, human pyramids and other formations can sometimes collapse, posing a danger to the participants.

Fifty-one accidents, 33 injured students, including six with broken bones, since August were enough for this city's mayor to reiterate a call for suspending coordinated gymnastic formations by elementary and junior high school children.

The accidents, tallied by the city's education board, occurred during practice sessions for formations to be featured in autumn sports festivals.

"It's not appropriate to continue allowing such dangerous performances," Kobe Mayor Kizo Hisamoto said at a meeting Oct. 17 of the city's comprehensive education council.

In August, Hisamoto requested in writing that the board halt such activities at schools, following a number of accidents in recent years.

According to the board's final tally submitted to the council the same day, there have been 66 accidents since April at municipal elementary and junior high schools, with 48 students injured.

The board said it will discuss the issue at a review conference with experts.

Over the three years through fiscal 2018, there were a total of 123 accidents involving broken bones suffered while performing the formations at the city's elementary and junior high schools.

The mayor repeatedly called for suspending the activities on Twitter, urging the board to be bold and halt the practice.

However, the board allowed the schools to continue performing the formations after requiring them to strengthen safety measures.

The safety of performing the gymnastic formations has been a controversial topic nationwide. The board of education in Akashi, Hyogo Prefecture, announced Oct. 16 that it plans to stop allowing the formations in the next fiscal year.