PARIS, France (AFP) — Tributes poured in from across the world Monday for the victims of the Orlando massacre, with global landmarks swathed in rainbow colours as people rallied behind the stricken gay community.

In the outpouring of solidarity similar to that seen after the Paris and Brussels attacks, political and religious leaders lined up to condemn the worst mass shooting in US history and to reject homophobia.

US President Barack Obama condemned the shootings in the Florida city as “an act of terror and an act of hate” and ordered flags at half-staff.

Pope Francis voiced shock at the “homicidal folly and senseless hatred” of slain gunman Omar Mateen, who gunned down 49 people at a gay nightclub in an attack claimed by the Islamic State group.

Joining the chorus of tributes, Paris Mayor Anne Hidalgo said that the Eiffel Tower would be lit up Monday night in the colours of the rainbow in memory of the victims.

“Paris is with Orlando,” the mayor of the French capital, which is still recovering from the November jihadist attacks in which 130 people were killed, tweeted along with a rainbow-coloured heart.

On Sunday, the spire of One World Trade Center in New York was already dyed red, orange, yellow, green, blue and purple, as was a sign in giant letters spelling Toronto in a square in the Canadian city.

“This is pride. Toronto stands in solidarity with the LGBTQ community around the world,” Toronto Mayor John Tory tweeted.

– #Loveislove –

Social media were flooded with messages condemning the attack using anti-homophobia hashtags #loveislove or #lovewins. Some posted images of a black ribbon or a ribbon combining the US and rainbow flag colours.

Following the latest in a string of mass gun killings in the United States that have claimed more than 1,000 lives in the past two years, Obama said the FBI was “appropriately investigating this as an act of terrorism”.

“Although it’s still early in the investigation, we know enough to say that this was an act of terror and an act of hate,” he said.

German Chancellor Angela Merkel said tolerance must prevail.

“Although such deadly attacks cause profound sadness in us, we are resolved to continue with our open and tolerant lifestyle,” she told German television on the sidelines of a visit to China.

While most leaders avoided polemical statements, the foreign minister of Lithuania, Linas Linkevicius, tweeted that the attack posed a “challenge for us all & #Muslims of the world.”

“How long bunch of cowards will hide under religion&kill in the name of #Islam?” he asked.

In a statement from the Vatican, the pope lamented the tragic loss of life.

The attack “caused in Pope Francis, and in all of us, the deepest feelings of horror and condemnation… before this new manifestation of homicidal folly and senseless hatred”, the statement said.

– ‘Stop hate’ –

On Sunday, hundreds gathered in New York’s Greenwich Village to leave flowers, candles and letters beside a sign reading “Stop Hate.”

In London, the PinkNews website said bars in the Soho district, which also has a thriving gay scene, would close on Monday evening and that customers would be invited onto the street to hold hands.

French President Francois Hollande reacted “with horror” to the Orlando attack, issuing a statement extending the “full support of France and the French people” during the ordeal.

Belgium’s Prime Minister Charles Michel also tweeted his condolences over the attack, which comes two-and-and-half months after dual strikes by jihadists on Brussels’ airport and metro killed 32 people.

“Deeply saddened by the loss of so many innocent lives in Orlando shooting. We join families in their grief,” he said.

Afghan President Ashraf Ghani also condemned the attack carried out by a suspected US-born 29-year-old of Afghan descent with a reputation for violence and homophobia.

“I unequivocally condemn the horrific attack in Orlando, Florida, USA. Nothing can justify killing of civilians,” Ghani tweeted.

In Britain, Prime Minister David Cameron and the royal family also issued statements condemning the violence.

Israeli Prime Minister Benjamin Netanyahu said his country “stands shoulder to shoulder with the United States at this moment of tragic loss.”

The leaders of Russia and China also sent messages of support.

Chinese President Xi Jinping called Obama to express his “sincere condolences to the American people”, the Chinese foreign ministry said.

Russian President Vladimir Putin, whose country has been condemned for attacks on gays, called the killings “a barbaric crime”.