released on 28 March 2010. Moncayo was released on 30 March 2010. On 13 June 2010, Colombian troops rescued Police Colonel Luis Herlindo Mendieta Ovalle, Police Captain Enrique Murillo Sanchez and Army Sergeant Arbey Delgado Argote in an event known as Operation Chameleon, twelve years after the individuals were captured; Argote was kidnapped on 3 August 1998. Ovalle and Sanchez were kidnapped on 1 November 1998. On 14 June, Police Lieutenant William Donato Gomez was also rescued. He was also kidnapped on 3 August 1998. Santos presidency (2010–2018) 2010–2011: Increased violence President Juan Manuel Santos began his term with a suspected FARC bomb-blast in Bogotá. This followed the resolution of the 2010 Colombia–Venezuela diplomatic crisis which erupted over outgoing President Álvaro Uribe's allegations of active Venezuelan support for FARC. In early September 2010, FARC-EP attacks in the Nariño Department and Putumayo Department in southern Colombia killed some fifty policemen and soldiers in hit-and-run assaults. According to a December report by the Corporación Nuevo Arco Iris NGO, 473 FARC-EP guerrillas and 357 members of the Colombian security forces died in combat between January and September 2010. An additional 1,382 government soldiers or policemen were wounded during the same period, with the report estimating that the total number of casualties could reach 2,500 by the end of the year. Nuevo Arco Iris head León Valencia considered that FARC guerrillas have reacted to a series of successful military blows against them by splitting up their forces into smaller groups and intensifying the offensive use of anti-personnel land mines, leading to what he called a further "degradation" of the conflict. Valencia also added that both coca crops and the drug trade have "doubled" in areas with FARC-EP presence. Researcher Claudia López considered that the Colombian government is winning the strategic and aerial side of the war but not the infantry front, where both the FARC-EP and ELN continue to maintain an offensive capacity. The International Crisis Group claimed that the military offensives carried out under former President Álvaro Uribe and President Juan Manuel Santos had led to the number of FARC-EC combatants being reduced to around 7,000, less than half the 20,000 combatants estimated to have been employed by the FARC-EC in the early 2000s. The same organisation also stated that the military offensive had been able to reduce FARC territorial control and push guerillas to more remote and sparsely populated regions, often close