Original sentence: The attack was the deadliest since December 2007 and was the second bombing in Spanish territory in two days after a similar incident in Burgos in Northern Spain the previous day: that attack had not brought about any fatalities
Edited sentence: The attack was  blamed on Basque separatist group Euskadi Ta Askatasuna (ETA).The attack was the deadliest ETA attack since December 2007 and was the second bombing in Spanish territory in two days after a similar incident in Burgos in Northern Spain the previous day: that attack had not brought about any fatalities