ISLAMABAD- Interior Ministry and intelligence agencies issued security alert for twin cities and Lahore before fruit market blast in Islamabad.According to reports, the Intel agencies warned that groups opposing Taliban dialogue may attempt to disturb law and order to exert pressure on government. However, the police failed to ensure security despite several alerts, the sources said. They further said that the overall security wasn't satisfactory due to the delay in appointment of DG National Crisis Management Cell and IG Islamabad police. On the other hand, it was revealed that highly explosive material RDX was used in the fruit market blast. The investigation was underway while police had not reached any conclusion as yet. It is important to mention that at least 26 people were killed while over 90 others injured in a blast at fruit market in Islamabad on Wednesday.