Abdel Moneim Aboul-Fotouh, a high-ranking Brotherhood member, was one of the people detained in the early morning raid, along with two other senior leaders.
"That's really a shame that Aboul-Fotouh was one of those detained, especially because he's considerend one of the most moderate leaders in the Brotherhood," Kamal Helbawi, the founder of the Muslim Association of Britain, said.
He told Al Jazeera: "He was also the secretary-general of the Arab Union for Medical Doctors and that's why hundreds of the union's members are angry because of his arrest specifically."
Helbawi, who is also a former spokesman for the Muslim Brotherhood, said: "Arrests in Egypt against the Brotherhood have become a routine and the government is trying really hard to send them away from the track of political life in Egypt."
The Brotherhood, which was founded by Hassan al-Banna in 1928, began as a religious, political movement but now holds a fifth of the seats in Egypt's parliament representing the largest bloc after the ruling party headed by Hosni Mubarak, the coutnry's president.
Although it is banned as an organisation, its members are allowed to run in elections as independents.