ADDIS ABABA June 23 (Reuters) - An air strike killed at least 43 people in the town of Togoga in Ethiopia"s Tigray region on Tuesday, a medical official told Reuters, after residents said new fighting had flared in recent days north of the regional capital Mekelle. Ethiopian military spokesman Colonel Getnet Adane did not confirm or deny the incident. He said air strikes were a common military tactic and that government forces do not target civilians. The bomb hit a market at around 1 p.m., according to a woman who said her husband and 2-year-old daughter had been injured. "We didn"t see the plane, but we heard it," she told Reuters on Wednesday. "When the explosion happened, everyone ran out. After a time we came back and were trying to pick up the injured." The woman said the market had been full of families, and she did not see any armed forces in the area. "Many, many" people had been killed, she said. Reuters could not independently verify her account. She and other sources asked not to be identified for fear of reprisals. The medical official confirmed at least 43 fatalities, citing witnesses and first responders. A spokesperson for Prime Minister Abiy Ahmed and the head of a government task force on Tigray did not respond to requests for comment. The U.S. State Department said it was concerned by reports of civilian deaths in the market attack and urged Ethiopian authorities to ensure full medical access for all the victims. "We also call for an urgent and independent investigation, as well as remedial action, to hold those responsible for this attack accountable," State Department spokesman Ned Price said in a statement. U.N. Secretary-General Antonio Guterres is deeply alarmed by the reports of civilian casualties, U.N. spokesman Stephane Dujarric told reporters in New York. "We have requested access to the area to assess the situation and see how we can provide assistance," Dujarric said. "The situation in the area remains very, very volatile." The airstrike happened as Ethiopian officials counted ballots from national and regional parliamentary elections held this week in seven of the nation"s 10 regions.No voting was held in Tigray, where the military has been battling forces loyal to the Tigray People"s Liberation Front (TPLF), the region"s former ruling party, since November. Security concerns and problems with ballot papers also delayed voting in two other regions. Residents reported that TPLF forces had entered several towns north of Mekelle in the past three days, withdrawing from one of them within hours. AMBULANCES BLOCKED The official and two other health workers helping with the response in Togoga told Reuters on Wednesday that Ethiopian soldiers were blocking the main road from Mekelle to the town and preventing ambulances from reaching the scene. "Patients are dying right now," the official told Reuters around midday. He said two ambulances had been able to reach the town via a back road late on Tuesday but did not have the necessary equipment and were not allowed to leave. He said the teams had counted at least 43 dead, and 44 critically wounded patients needing treatment. One medical worker told Reuters he had tried to reach the scene six times over two days. Finally around several ambulances reached Mekelle"s Ayder Referral Hospital as night fell. The oldest victim who arrived was 62, and the youngest was six, a doctor there told Reuters. Many had serious injuries, including a man whose brain was exposed, he said. A doctor who had stayed at the scene overnight told Reuters it was "terrible" and shared pictures of people too wounded to move wrapped in blankets against the cold. "We heard screaming and crying coming from houses where people died - one family lost four members," she said. "All the houses around the market were flattened, apples and tomatoes lying everywhere." "Many people who were injured died before we could reach them ... I felt so hopeless." Military spokesman Getnet denied that the military was blocking ambulances.