Three police officers have diedin a bomb blastat a police station in Colombia, after thousands gathered for renewed protests in the capital, Bogota.Ten other officers were also injured in the explosion in Santander de Quilichao, a town in the southwestern province of Cauca which is a hotspot for drug trafficking and violence.It comes after three people were killed on Thursday as more than 250,000 people marched in a national strike to express growing discontent with President Ivan Duque's government.Their grievances include rumoured economic reforms that the president has denied and anger at what protesters call a lack of government action to stop corruption and the killing of human rights activists.Image:Some protesters in Bogota's Bolivar Plaza banged pots and pansThousands gathered on Friday afternoon in Bogota's Bolivar Plaza for a "cacerolazo" - a traditional Latin American expression of protest in which people bang pots and pans."We are here to keep protesting against the Duque government," said 25-year-old student Katheryn Martinez, as she clanged a pot with a fork."It's an inefficient government that kills children and doesn't acknowledge it," she said, referring to a recent bombing targeted at rebels that killed eight teenagers and prompted the former defence minister to resign.The crowd was quickly dispersed by tear gas, but some protesters regrouped on the streets while people in other neighborhoods gathered for cacerolazos.Image:Police officers in riot gear have used tear gas to disperse the protestersSeveral supermarkets in the city's south were looted as protesters, many of them masked, burned items in the street and blocked roads.In a televised address on Friday evening, President Duque said some people were taking advantage of the protests to "sow chaos".He added: "From next week I will start a national conversation that will strengthen the current agenda of social policies."He said the dialogue would "permit us to close social gaps, fight corruption more effectively and build, between all of us, peace with legality".Image:President Ivan Duque said some protesters were 'sowing chaos'An investigation into the three deaths in Valle del Cauca province on Thursday were being investigated, Defence Minister Carlos Holmes Trujillo said.He added that while the vast majority of Thursday's marchers were peaceful, 98 people were arrested, and 122 civilians and 151 members of the security forces were injured.The protests have coincided with demonstrations elsewhere in Latin America, from anti-austerity marches in Chile, to protests over vote-tampering allegations in Bolivia that led President Evo Morales to resign, and inflamed tensions in Ecuador and Nicaragua.