Image copyright Getty Images Image caption Eleven people have died and 5,000 have been hospitalised

A man dressed in a mascot costume at an amusement park is one of least 11 people who have died as a result of a heatwave sweeping Japan.

The 28-year-old died from heatstroke on Sunday evening in Hirakata Park, Osaka, after dancing for 20 minutes while wearing a 16kg (35lb) outfit.

In response, the park has cancelled all events using mascot costumes.

Official figures revealed more than 5,000 people sought hospital treatment due to the heatwave in the last week.

According to Kyodo news agency, more than 50% of those hospitalised were aged 65 and over.

Temperatures are expected to remain higher than average for the next week.

The part-time worker at Hirakata Park was dressed in an outfit to play the role of a fairy character who lives in the park, police were quoted by the Asahi Shimbun newspaper as saying.

He had been rehearsing on stage with other staff members when he fell ill at around 19.30 (10:30 GMT) on 28 July. The highest temperature in Hirakata that day was 33.2C (91.76F), and by 20:00 it was 28.7C, the newspaper added.

The worker lost consciousness and was rushed to hospital where he died.

In a statement, owners of the park, Keihan Leisure Service promised to "find the cause" of the incident and "work to prevent it from happening again", the Japan Times said.

The highest temperatures, of around 37C, on Monday were recorded in Gifu Prefecture, central Japan, and Iwate Prefecture in the north of the country, the newspaper also reports. Some 80% of the country's 926 temperature monitoring posts marked 30C or above, according to Japan's meteorology agency.

It's not the first time Japan has been gripped by a deadly heatwave. In July last year, the country's weather agency declared a heatwave a natural disaster after 65 people died from heat-related deaths within one week.