Parliament of Catalonia
Separatists declared victory in Thursday's regional election.
Puigdemont left for Belgium after Catalonia’s regional government was sacked.
It's one of the biggest pro-unity rallies amid Catalonia's independence crisis.
The government voted to strip Catalonia of its autonomy less than an hour after the region declared independence.
WHAT'S HAPPENING
If Spain's prime minister invokes Article 155 of the 1978 constitution, it would not be fully effective until at least early next week.
Metro stations were closed in Barcleona as state workers walked out across Catalonia.