警

警笛

jǐng dí

siren

边防警察

biān fáng jǐng chá

border police

防暴警察

fáng bào jǐng chá

riot police

电子警察

diàn zǐ jǐng chá

traffic camera

电警棍

diàn jǐng gùn

stun baton

预警

yù jǐng

warning

预警机

yù jǐng jī

early warning aircraft system, e.g. US AWACS

预警系统

yù jǐng xì tǒng

early warning system

香港警察

xiāng gǎng jǐng chá

Hong Kong Police Force (since 1997)

骑警

qí jǐng

mounted police (on horse or motorbike)

骑警队

qí jǐng duì

mounted police detachment (on horse or motorbike)

中国人民武装警察部队

zhōng guó rén mín wǔ zhuāng jǐng chá bù duì

Chinese People's Armed Police Force (PAP, aka CAPF)