Venezuelan opposition leader Leopoldo Lopez arrived in Madrid on Sunday after fleeing the Spanish ambassador’s residence in Caracas, Spain’s Foreign Ministry said. Mr Lopez, a political prisoner since 2014, had been taking refuge in the Spanish embassy since April last year after a botched uprising against President Nicolas Maduro that he led alongside National Assembly head Juan Guaido. Mr Lopez was reunited on Sunday with his family, the Spanish Foreign Ministry said. His wife and children have lived in Madrid since last year. Mr Lopez’s decision to leave the embassy was “personal and voluntary", the ministry said. The ministry also condemned what it said was the detention of some of its embassy workers over Mr Lopez’s departure. It will be a blow to an already weakened opposition, which under Mr Guaido’s stewardship has failed to deliver the quick transition to power promised at the start of last year. “After two years of a continuous struggle, it seems that Mr Maduro is stable and the opposition cannot find answers,” political analyst Dimitris Pantoulas said in Caracas. “Mr Lopez considers that it’s better to continue his fight outside, from exile, something that could also happen with Mr Guaido.” Venezuela said it was investigating what it called a “flagrant violation” of the Vienna Convention on Diplomatic Relations by Spanish ambassador Jesus Silva in organising Mr Lopez’s escape. “Spain participates actively in the illegal escape of a dangerous delinquent and decides to receive him in its territory,” the government said on Foreign Minister Jorge Arreaza's Twitter account. While the US and other countries consider Mr Guaido to be Venezuela’s legitimate president, an influential Trump administration official secretly met a representative of Venezuela’s regime in Mexico City in September to try to negotiate Mr Maduro’s departure. Sentenced to almost 14 years in prison on charges including arson and instigating violence after leading anti-government protests, Mr Lopez was released on house arrest in 2017 with orders to remain quiet. From there, he helped to orchestrate the rise of Mr Guaido, who he met more than a decade ago during protests against the late Venezuelan president, Hugo Chavez.