Nampula, being the third-largest city in Mozambique, has a fair share of safety concerns. Like many large cities, it experiences petty crime such as theft and pickpocketing which can escalate at night. It's advisable to take precautions including avoiding deserted areas and exposure of valuables, moving in groups when possible, and using reliable transportation. Sexual harassment can be an issue at times, hence it's important to dress modestly respecting local norms. Police corruption might also be an issue. You should always keep emergency numbers at hand. Unfortunately, necessary infrastructure like street lighting may be lacking making some areas feel insecure. Check travel advisories often and stay updated on the local situation.