(http://news.bbcimg.co.uk/media/images/79384000/png/_79384245_nigeriakanomaiduguri4641114.png) Several men then opened fire on the crowd, killing more people. Three of the gunmen were caught and killed on the spot, our correspondent says.
Most victims were men or boys with blast injuries and severe burns.
BBC Hausa editor Mansur Liman said one witness at a local hospital had described the scenes there as being the most horrible he had ever seen.
Boko Haram has stepped up attacks against civilian targets since the Nigerian military launched an offensive last year.
The group carries out almost daily attacks mostly in the north-east of the country. Also on Friday, the security forces said they had foiled an attempt to attack worshippers in the north-eastern city of Maiduguri, defusing six bombs planted in a mosque and a nearby market.
The militants were also behind the kidnapping of more than 200 schoolgirls from Chibok in Borno state this year, an act that sparked international outrage.
(http://news.bbcimg.co.uk/media/images/75306000/jpg/_75306515_line976.jpg) (http://news.bbcimg.co.uk/media/images/79238000/jpg/_79238273_79002708.jpg) Boko Haram leader Abubakar Shekau has declared an Islamic state in the north-east Who are Boko Haram?
- Founded in 2002
- Initially focused on opposing Western education - Boko Haram means "Western education is forbidden" in the Hausa language
- Launched military operations in 2009 to create Islamic state
- Thousands killed, mostly in north-eastern Nigeria - also attacked police and UN headquarters in capital, Abuja
- Some three million people affected
- Declared terrorist group by US in 2013
Who are Boko Haram? (http://www.theinfostride.com/news/world-africa-13809501)
Profile: Boko Haram leader Abubakar Shekau (http://www.theinfostride.com/news/world-africa-18020349)
Source: BBC