The 6ft 5in bodyguard Gaz Batley was hospitalised after being shot in the throat during a game in Manchester, reports The Sun.
Batley is now reportedly recovering in bed but is still unable to speak due to the injury.
"Gaz is 6ft 5in and 18st so he's their biggest asset when it comes to protecting them," a friend of the group said. "He's not hard to miss so he was the biggest target of the day.
"Oritsé is mad about paintball and prides himself on being the best. But there's no way he meant to hit Gaz in the throat.
"He was devastated when he realised what had happened and he hasn't stopped apologising since."
The singer's bandmates Aston Merrygold, Marvin Humes and JB Gill have since joked that Batley will get his own back on Williams when he recovers.
"The lads know Gaz won't forget this," the source added. "He's laughed it off, but undoubtedly there will be some prank or payback."
JLS will reportedly hire an ex-MI5 agent to help set up Marvin Humes's stag do later this year.
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