The deadly bomb attacks on the Belgian capital claimed by the Islamic State of Iraq and the Levant (ISIL) group have prompted a huge and varied reaction on social media.
Hashtags referring to the attacks trended worldwide on Twitter, picking up millions of mentions and reaching tens of millions more users.
On Facebook users changed their display pictures to ones featuring the Belgian flag in solidarity with victims of the bombings.
Initial posts focused on the explosions at Zaventem Airport and Maelbeek metro station, with those at the scene tweeting footage of the aftermath of the attacks.
Later reactions were varied with most expressing their horror at the killings but some using the attacks to support their political views and debate the issue of Islam in Western countries.
|Brussels hashtags trended around the world after the attacks [Al Jazeera]
In the UK -where there is an upcoming referendum on the country's continued membership of the EU - there was an angry reaction when Daily Telegraph columnist Allison Pearson referred to Brussels as the "Jihadist capital of Europe", adding the UK was safer out of the Union.
Most Twitter users responding to her post condemned Pearson for politicising the attacks but a few praised her for "speaking the truth" .
Brussels is one of the seats of the European Parliament and houses many EU buildings. In the UK the name of the city is often used by Eurosceptics as a byword for the EU.
The anger was not reserved for Pearson alone. Comments by US Republican presidential candidates Ted Cruz and Donald Trump were also subject to controversy.
Cruz's suggestion that police securitise Muslim areas and Trump's comments about using torture to prevent future attacks prompted condemnation and praise alike.
In the US Republican primaries a lot of debate has focused on Europe's ongoing refugee crisis and the threat the mainly Muslim migration poses to Western states.
A familiar theme following attacks like the ones in Brussels and earlier in Paris is debate surrounding the future of Islam and Muslims in Europe.
ISIL (also known as ISIS) has claimed responsibility for both attacks, evidence critics of Islam say is evidence of the threat posed by Muslims.
The hashtag #StopIslam -started by critics of the religion- was quickly flooded with messages of solidarity with Muslims and refusal to let ISIL divide communities in the West along religious lines.
As of Wednesday morning, the overwhelming majority of tweets using the hashtag were condemnations of Islamophobia.
Another prominent theme following the attacks was the allegedly disproportionate emphasis media outlets placed on covering them over similar attacks in Turkey and other countries.
Many users pointed out that the attacks in Istanbul by ISIL just a few days earlier had not received the same amount of coverage as the ones in Belgium, with some going further by stating this was due to bias against non-Europeans.
Other users suggested the disparity was because attacks in Belgium - a European country, with a similar culture to others in the West - would resound more emotionally with others living in the West.
Source: Al Jazeera