Two men wielding hatchets chased children through a Co Derry street last night.
The incident happened at Clonmeen Drive in Strathfoyle shortly before 10pm.
Officers used a taser gun on a 44-year-old man who remains in custody. A 42-year-old man was also arrested but later released on police bail.
Anyone who witnessed this incident or who has any information is asked to contact police in Waterside on 0845 600 8000 or to contact Crimestoppers anonymously on 0800 555 111.