At least seven people have been killed and 140 injured as thousands took to the streets in protest after Sudan’s military seized power from a transitional government.

Thousands of people joined rallies against the military takeover on the streets of the capital, Khartoum, and its twin city of Omdurman after security forces arrested interim Prime Minister Abdalla Hamdok and other senior officials early on Monday morning. A health official said at least seven were killed by gunfire.

The leader of the takeover, General Abdel Fattah al-Burhan, dissolved the military-civilian Sovereign Council that had been set up to guide the country to democracy following the overthrow of longtime leader Omar al-Bashir in a popular uprising two years ago.

Al-Burhan, who is also the head of the power-sharing governing council, declared a state of emergency across the country, saying the armed forces needed to ensure safety. He promised to hold elections in July 2023 and hand over to an elected civilian government then.

"What the country is going through now is a real threat and danger to the dreams of the youth and the hopes of the nation,” he said.

The governments of the United States, the United Kingdom, and Norway on Monday night issued a statement expressing deep concern about the situation, condemning the suspension of democratic institutions and calling for the release of those arrested.

"The actions of the military represent a betrayal of the revolution, the transition, and the legitimate requests of the Sudanese people for peace, justice and economic development,” the so-called Troika countries said in a joint statement.

Hamdok, an economist and former senior UN official who was appointed as a technocratic prime minister in 2019, was moved to an undisclosed location after he refused to issue a statement in support of the coup, the information ministry said.

Thousands of Sudanese opposed to the takeover took to the streets and faced gunfire near the military headquarters in Khartoum. In Omdurman, protesters barricaded streets and chanted in support of civilian rule.

The Forces of Freedom and Change, Sudan’s main opposition coalition, called for civil disobedience and protests across the country and demanded that the transitional military council transfer power back to the civilian government.

Sudan’s central bank employees said they went on an immediate strike in rejection of the military coup, the Sudanese information ministry wrote on its page on Facebook.

Speaking to Al Jazeera, Hala al-Karib, a Sudanese activist for women’s rights in the Horn of Africa, said that Sudan was going through "very grim moments in its history” as it stands at "a crossroads”.

She called on the international community to pressure the military to respect the Constitution and agreements with the civilian council.

"The military has dishonoured its agreement with the civilian government by detaining the prime minister and several cabinet ministers,” said al-Karib. "The Sudanese people don’t know if they are safe or not.”