neighbouring Cameroon and Chad where they were to be sold into marriages at a price below a dollar each. The abduction of another eight girls was reported later. These kidnappings raised public protests, with some protesters holding placards bearing the Twitter tag #BringBackOurGirls, which had caught international attention. The Guardian reported that the British Royal Air Force conducted Operation Turus in Nigeria in April in response to the Chibok kidnapping. A source involved with the operation told The Observer that "The girls were located in the first few weeks of the RAF mission", and that "We [RAF] offered to rescue them, but the Nigerian government declined", this was because it viewed any action to be taken as a "national issue", and for it to be resolved by Nigerian intelligence and security services, the source added that the girls were then tracked by the aircraft as they were dispersed into progressively smaller groups over the following months. Several countries pledged support to the Nigerian government and to help their military with intelligence gathering on the whereabouts of the girls and the operational camps of Boko Haram. On 13–14 May, Boko Haram ambushed Nigerian soldiers who were searching for the kidnapped girls. Jos bombings On 20 May, two bombs in the city of Jos, Plateau State, Nigeria, were detonated, killing at least 118 people and injuring more than 56 others. The bombs exploded 30 minutes apart, one at a local market place at approximately 3:00 and the second in a parking lot next to a hospital at approximately 3:30, where rescuers responding to the first accident were killed. Though no group or individual has claimed responsibility, the attacks have been attributed to Boko Haram. First responders were unable to reach the scenes of the accidents, as "thousands of people were fleeing the scene in the opposite direction". The bombs had been positioned to kill as many people as possible, regardless of religion, which differed from previous attacks in which non-Muslims were targeted. The bombers were reported to have used a "back-to-back blast" tactic, in which an initial bomb explodes at a central location and another explodes a short time later with intent to kill people working to rescuing the wounded. Maiduguri bombings In 2014, Boko Haram militants increased their attacks on cities and towns in northern Nigeria and captured part of the country's northeast. These attacks included bombings in Maiduguri in January,