A town in western Japan has been flooded with complaints and threatening phone calls over its program for administering coronavirus vaccinations to people between the ages of 12 and 15.

Amid the massive backlash against the COVID-19 vaccination program that started the previous day, the town of Ine in Kyoto Prefecture on Monday closed its call center for inquiries and consulted with police.

According to the town, people who called the center were critical of the vaccination plan, saying there were risks for children receiving COVID-19 vaccinations and that young women could become infertile as a result of the shots.

Some of the callers accused the town of "committing murder" or made death threats against staff members. The volume of protest calls overwhelmed the center's capacity, forcing the town to close it.

After the center stopped taking calls, more than 100 additional protest calls were made to the town government. All of these calls were from outside the town, suggesting the callers were not local residents.

The town also received protest messages via more than 20 emails and eight faxes.

Compared with other developed countries, Japan lags behind in COVID-19 vaccinations, despite the start of the Tokyo Olympics being less than two months away.