Never attempt to make your own devices and do not purchase or use any kits that are advertised for making fireworks.

千万不可尝试自制设备，不要购买或使用被大肆宣传用来制作烟花的工具。

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Officers are trying to ascertain whether the noise and damage has been caused by fireworks or similar homemade devices.

BBC: Denbigh 'explosions' prompt police appeal

He said he experimented with pyrotechnic devices and helped organise displays for the local community during World War II, at a time when fireworks were not readily available.

BBC: Cambridgeshire