South American leaders closed ranks around Venezuelan acting President Nicolas Maduro, the late Hugo Chavez\'s chosen successor, as Chavez lay in state Thursday. Argentine President Cristina Fernandez de Kirchner, Bolivian President Evo Morales and Uruguayan President Jose Mujica joined Maduro, 50, in paying respects to Chavez at his open wooden casket at the military academy in Caracas. Chavez, 58, died Tuesday after suffering from cancer for nearly two years, the government said. The South American leaders who showed support for Maduro had walked with the former bus driver and union organizer alongside the black hearse carrying Chavez\'s flag-draped casket through the streets of Caracas, the capital. The leaders were surrounded by hundreds of soldiers in green fatigues and tens of thousands of civilians wearing the yellow, blue and red of the national colors. When Chavez\'s body arrived at the military academy from the Carlos Aveledo Military Hospital 7 hours later -- a 5-mile trip -- it was piled high with flowers, caps and T-shirts thrown by the surging crowds, The Miami Herald reported. Chavez -- whose career included a failed 1992 coup, a successful 1998 election campaign and then 14 years as the three-times re-elected president of the oil-rich nation -- is to lie in state until a state funeral Friday. Maduro is widely expected to be the official candidate to succeed Chavez. Opposition leader Henrique Capriles, 40, who lost to Chavez in October\'s presidential vote, is expected to be the opposing candidate. Maduro signed a decree, calling for seven days of official mourning, as \"Acting President of the Republic,\" the state-sponsored Correo del Orinoco newspaper reported Wednesday. But an Information Ministry spokesman said Maduro had not been sworn in yet. The spokesman told The Wall Street Journal he didn\'t know when the ceremony would take place. A handful of lawmakers said rival Chavez loyalist National Assembly President Diosdado Cabello was constitutionally required to be acting president following Chavez\'s death until a vote is held. The vote is to be held within 30 days. But Attorney General Cilia Flores, Maduro\'s wife, said on state television Maduro was rightfully in line to assume the interim presidency while an election is called. \"In the moment that [Chavez] disappears physically, immediately and automatically ... the vice president is in charge,\" she said. She said her husband also had the blessing of Chavez to lead the nation. Many businesses remained closed Wednesday, partly out of mourning for Chavez and partly out of fear his passing could cause unrest, the Journal said.