Egyptian-born German researcher Atef Botros said Tuesday he "will not be silenced about the injustices" after authorities denied him entry to Egypt, stressing that he is entitled to enter the country he was “born and raised in” regardless of his stance.

“My stance on the [Egyptian] regime, the use of torture, detention, forced disappearances, and killing of protesters won’t change,” the founder of Mayadin Al-Tahrir NGO said in a Facebook statement, highlighting the beliefs that he says have caused him to be denied entry.

Botros was detained upon arrival at Cairo’s International Airport late Friday, questioned by the authorities, and deported to Germany on Saturday.

Egyptian authorities did not comment on denying entry to Botros, who was born in Egypt to Egyptian parents but, according to his statement, was naturalised as a German citizen in 2008.

According to German law, he was required to give up his Egyptian nationality. Botros explained in the statement that he respects Germany, where he studied and worked in academia, but his feelings for and affiliations with his first country, Egypt, did not change.

He added he was being monitored because of his anti-Egyptian regime statements in the media, especially during Egyptian President Abdel-Fattah El-Sisi's visit to Berlin last year, as well as his organisation of rallies in Germany against El-Sisi’s regime.

Botros added that during his detention at the airport authorities pressured him to obtain names and information on his family members and friends, which he refused to do.

"Any police state can prevent someone from entering his country, but they cannot prevent him from dreaming of changing it," Botros added.

Botros is a professor in Germany's Marburg University Centre for Near and Middle East Studies. His NGO, Mayadin Al-Tahrir, aims to enhance the capacities of marginalised groups in Egypt, in particular the women and youth of Matariya district.

Critics of Botros’s detainment and deportation accused the Egyptian Embassy in Berlin of sending Egypt security reports on Egyptian political activists in Germany, leading to their arrest back home.

The accusations cited the case of Egyptian journalist Ismail Alexandrani, who was detained at the airport in December 2015 upon arrival from Germany.

Alexandrani is currently detained pending trial on charges of “broadcasting false news” and joining the banned Muslim Brotherhood group.

The Egyptian Embassy in Berlin released a statement on Monday saying these allegations are “fabrications” and show “a complete ignorance of the basic roles of Egyptian embassies in defending Egypt's national interests and serving its expats."