Twin explosions hit Nigerian city
Twin explosions have rocked the central Nigerian city of Jos, killing about 20 people.
The blasts occurred as store owners were shutting their shops and Muslims were preparing for prayers.
Witnesses said one blast went off at an outdoor food stand and the other at a nearby marketplace in the centre of the city.
In May, twin car bombs in the Jos marketplace killed at least 130 people.
Those attacks were blamed on Islamic extremists from the Boko Haram group.
There was no immediate claim of responsibility for the attack but it bore all the signs of Boko Haram.
The attacks have been seen as an attempt to ignite fighting between Muslims and Christians. Jos is in Nigeria's Middle Belt, where the mainly Muslim north and predominantly Christian south meet and violence between the two groups occurs often.
In northern Kano, Nigeria's second largest city, police commissioner Aderenle Shinaba told reporters they safely detonated a bomb hidden in a handbag. The bag had been planted in a supermarket favoured by foreigners.
Separately, police in Kano arrested a teenage girl wearing a jacket primed with explosives.
Several bombs in recent months have been detonated by female suicide bombers, raising fears that Boko Haram is using some of the hundreds of kidnapped girls and young women for its attacks.
Twin bomb blasts killed at least 102 people at the main mosque in Kano on November 29, when gunmen also shot at people trying to escape.
At least 75 people have been killed in bomb blasts by female suicide bombers in recent weeks in Maiduguri, the north-eastern capital of Borno state that is the birthplace of Boko Haram.
The extremist group has taken over several towns and villages along the north east border with Cameroon, where it has declared an Islamic caliphate.
Thousands of people have died and 1.2 million have been forced from their homes in the five-year-old insurgency.