<Ul> <Li> 6th Pan-Northern Nigeria <Ul> <Li> Kawuri </Li> </Ul> </Li> <Li> Izghe </Li> <Li> Konduga & 1st Gwoza </Li> <Li> 1st Lake Chad </Li> <Li> 1st Buni Yadi </Li> <Li> 3rd Abuja </Li> <Li> 1st Nyanya </Li> <Li> Chibok </Li> <Li> 2nd Nyanya </Li> <Li> Gamboru & Ngala </Li> <Li> Jos </Li> <Li> Mubi </Li> <Li> 2nd Buni Yadi </Li> <Li> 2nd Gwoza </Li> <Li> 7th Pan-Northern Nigeria </Li> <Li> 8th Pan-Northern Nigeria </Li> <Li> Damboa </Li> <Li> Kogi </Li> <Li> 2nd Potiskum </Li> <Li> 2nd Kano </Li> <Li> Gumsuri </Li> <Li> Gombe </Li> <Li> 1st Cameroon </Li> <Li> Muse </Li> </Ul> <Li> 6th Pan-Northern Nigeria <Ul> <Li> Kawuri </Li> </Ul> </Li> <Ul> <Li> Kawuri </Li> </Ul> <Li> Konduga & 1st Gwoza </Li>

When did boko haram attacks start in nigeria