Taxis are seen on the street in Lisbon, Portugal, on April 29, 2013. Thousands of Portuguese taxi drivers drove their car into Lisbon on Monday in protest against government's decision to shift the transportation of non-emergency patients by them to firefighting department. (Xinhua/Zhang Liyun) 

Taxis are seen on the street in Lisbon, Portugal, on April 29, 2013. Thousands of Portuguese taxi drivers drove their car into Lisbon on Monday in protest against government's decision to shift the transportation of non-emergency patients by them to firefighting department. (Xinhua/Zhang Liyun) 

Taxis are seen on the street in Lisbon, Portugal, on April 29, 2013. Thousands of Portuguese taxi drivers drove their car into Lisbon on Monday in protest against government's decision to shift the transportation of non-emergency patients by them to firefighting department. (Xinhua/Zhang Liyun) 

Taxis are seen on the street in Lisbon, Portugal, on April 29, 2013. Thousands of Portuguese taxi drivers drove their car into Lisbon on Monday in protest against government's decision to shift the transportation of non-emergency patients by them to firefighting department. (Xinhua/Zhang Liyun) 

Taxis are seen on the street in Lisbon, Portugal, on April 29, 2013. Thousands of Portuguese taxi drivers drove their car into Lisbon on Monday in protest against government's decision to shift the transportation of non-emergency patients by them to firefighting department. (Xinhua/Zhang Liyun)