The United Kingdom is warning its citizens of a "high threat" of a terrorist attack in Nigeria around the Easter holiday.

The Foreign Office issued the updated travel warning Thursday, noting that a radical Islamist sect in Nigeria known as Boko Haram carried out attacks on Christmas Day. A sect-claimed car bombing at a Catholic church outside of Nigeria's capital that day killed at least 44 people.

The Foreign Office warning also advised against travel to seven states in Nigeria's Muslim north.

It offered no further details about the Easter threat.

Boko Haram is waging an increasingly bloody fight against Nigeria's weak central government. The sect's demands include implementation of strict Shariah law and the release of all its detained members.