Both mayors and their moderators can timeout a player. The mayor or moderator must be inside their town's borders for this to work. The player being timed out does not need to be in the town's borders.
The command is /timeout <player_name> [seconds]
Seconds is optional. If you don't send it with the command it will default to 10 minutes.
Example 1 /timeout xavier_robledo
Example 2 /timeout xavier_robledo 3600
Timed out players cannot chat in your town for the time you set.