A Ryanair flight scheduled to leave Lisbon for Rome on Friday was targeted with a threat, the airline said, while at least 11 flights were targeted in the Czech Republic and Bulgaria, according to AFP.
France also reported at least four of its flights were targeted by threats, however they all landed safely.
No explosives have been found on any planes as of Friday.
As airlines were dealing with this latest wave of threats, several media outlets, including RTÉ, were evacuated after similar warnings were made against them.
Staff at the Irish Independent newspaper and the Dublin offices of radio stations NewstalkFM and TodayFM, were also advised to leave their buildings and UK broadcaster Sky said it also received a security threat.
In a statement, gardaí (Irish police) said they were “aware of a threat made against media organisations here and in Europe”.
While no link has been established between the threats against airlines and media outlets, the Irish government has warned it is a “likely coordinated campaign of disruption”.
In a statement, it said: “Hoax threats such as these cause fear, distress and disruption to people going about their daily lives and activities; they achieve no positive purpose whatsoever. It is not known yet who is responsible for these threats, whether it is individuals or a centralised or co-ordinated effort.
Irish Prime Minister Micheál Martin described the situation as “worrying” and added his government’s first priority was the safety of the Irish public.
“Yesterday, there appeared to be coordinated efforts to disrupt air travel,” he said.
Martin told RTÉ it was not yet known if the threats had come from individuals or if it was a “coordinated attack” but said they were being taken seriously.
Ireland is scheduled to host two high-profile European Union meetings in Dublin next week.
Broadcaster Sky confirmed it had received a security threat, hours after RTÉ had evacuated its building.
The broadcaster, which is owned by Comcast, said in a statement read by a presenter on its news channel that the broadcaster had “carried out a security assessment and reported the matter to the relevant authorities”.
“The safety and security of our colleagues is our primary concern, and we are working closely with authorities to ensure our people and operations remain secure.”
Friday’s disruption comes after the Russian extremist group “Male State”, named in this week’s hoax bomb threats to Italian airports, denied any link to the false warnings.
Replying to the BBC Russian Service, an account on Telegram – one of several linked to the so-called “Male State” and its founder Vladislav Pozdnyakov – mocked any suggestion the group was involved in emailing the threats.
“What Male State? Where have you seen it? It hasn’t existed for many years,” the message on the channel reads. “If tomorrow they sign a [threat] letter, say, from Putin, will you then try to reach our president to ask your stupid question?”
