Azerbaijan arrested four people in connection with the attempted assassination of an anti-Iran lawmaker, who was shot and wounded last week, an Interior Ministry spokesman said.
Representative Fazil Mustafa, who has been highly critical of Iran, was receiving treatment in a hospital after being shot in the attack.
Mustafa's assistant, Ajdar Aliyev, told Reuters the politician was feeling well and expected to return to his home, which he said was under police guard, in the coming days.
The interior ministry spokesman declined to give details of the arrested suspects, saying a statement would be released later.
However, Azerbaijani media reported that one of the detainees, Hasan Ramez, is the brother of Hossein Ramez who previously threatened the deputy from his residence in Iran.
Meanwhile, the Foreign Ministry summoned the Iranian ambassador, Abbas Mousavi, in response to a memorandum sent by the Iranian embassy in protest against Azerbaijani media coverage about Iran.
Local Azertac news agency reported that the spokesperson of the Foreign Ministry, Aykhan Hajizada, disputed the claims made in the complaint.
Moreover, the Foreign Ministry handed the ambassador several articles published in Iranian media against Azerbaijan.
"Ambassador of Iran to Azerbaijan was informed that the insulting, false, defamatory and biased information about the Republic of Azerbaijan and its government officials regularly spread in the Iranian media, as well as well-known Iranian public and political figures' statements and speeches, undermine relations between our countries and further deepen misunderstandings," read the statement.
The misunderstandings arising in "our relations are constantly caused by the unilateral behavior and steps of the Iranian side, as well as the inadequate reciprocation by Iran of consistent and well-intentioned steps by Azerbaijan."
The Azerbaijani official urged the Iranian diplomat to "prevent the spread of false and biased information against Azerbaijan in Iranian media."
Relations between Azerbaijan and Iran had already been strained after an attack on Baku’s embassy in Tehran in January, which resulted in casualties.
Baku insisted it was a "terrorist attack," while Tehran claimed the attacker had "personal motives."
Relations between the two countries were also strained by military movements between Armenia and Azerbaijan around the disputed Nagorno-Karabakh region.
Tensions between the two oil-rich neighbors deepened after Azerbaijan sent an ambassador to Israel and opened an embassy there last week.
Last Friday, the Iranian Foreign Ministry condemned Israeli Foreign Minister Eli Cohen's statements regarding the agreement with his Azerbaijani counterpart on "forming a united front" against Iran. Baku denied making any statement against Tehran.