query: Has Sydney been under siege?
passage: 2014 Sydney hostage crisis
The 2014 Sydney hostage crisis, also known as the Sydney siege and Lindt Cafe siege,[12][13][14] occurred on 15–16 December 2014 when a lone gunman, Man Haron Monis, held hostage ten customers and eight employees of a Lindt chocolate café located at Martin Place in Sydney, Australia. Police treated the event as a terrorist attack at the time,[12][15] but Monis' motives were subsequently debated. However, the findings of the Coroner in 2017 deemed the event to be a terrorist attack.
passage: Siege of Wadi Deif (2014)
The Siege of Wadi Deif refers to the siege of two Syrian Army bases, Wadi Deif and Hamadiyah (both just outside Maarrat al-Nu'man), by rebel forces, during the 2014 Idlib offensive of the Syrian Civil War. The first siege of these two bases was broken by the Syrian Army on 18 April 2013. During the siege, rebels detonated several 'tunnel bombs' underneath Army positions surrounding the bases, which was similar to the tactics used during the First World War.