AMMAN, Oct 11 (Reuters) - A large bomb exploded in an area housing security and army compounds west of Umayyad Square in central Damascus on Thursday, opposition activists said.

Islamist groups Ahfad al-Rasoul and Ansar al-Islam said in a joint statement they planted bombs in a compound belonging to State Security in the area.

Syrian state television said a "terrorist explosion" had injured two people. Witnesses said soldiers in full combat gear were deployed in the area and all roads leading to Umayyad Square were cut.

Ansar al-Islam claimed responsibility for a bomb attack last month on the army's Chief of Staff headquarters in Umayyad Square, which started a large fire in the building.

Also on HuffPost:

Loading Slideshow...

  • A Syrian boy, who fled his home with his family due to fighting between government forces and rebels, stands near his tent at a refugee camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • An elderly Syrian woman, who fled her home with her family due to fighting between government forces and rebels, chants, "Allah," meaning God in Arabic, inside her tent at a refugee camp near the Turkish border, in Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • A Syrian woman, who fled her home with her family due to fighting between government forces and rebels, stands near her tent at a refugee camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • A Syrian man, who fled his home with his family due to fighting between government forces and rebels, plays with his nephew near their tent at a refugee camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • Syrian women, who fled their homes due to fighting between government forces and rebels, drink tea inside their tent at a refugee camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • Syrians, who fled their homes with her families due to fighting between government forces and rebels, sit in their tent at a refugee camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • Syrias, who fled their homes with their families due to fighting between government forces and rebels, take refuge at a camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • A Syrian woman, who fled her home with her family due to fighting between government forces and rebels, sits near her tent at a refugee camp near the Turkish border, in Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • A Syrian girl, who fled her home with her family due to fighting between government forces and rebels, flashes the victory sign at a refugee camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • A Syrian boy, who fled his home with his family due to fighting between government forces and rebels, plays near his tent at a refugee camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • Syrians, who fled their homes with their families due to fighting between government forces and rebels, wait for food distribution from an NGO at a refugee camp near the Turkish border, in Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)

  • A Syrian boy, who fled his home with his family due to fighting between government forces and rebels, holds a plate with food to eat at a refugee camp near the Turkish border, Azaz, Syria, Sunday, Oct. 7, 2012. (AP Photo/ Manu Brabo)