Hamburg, July 3 (RHC)-- Thousands attended a rally in the northern German city of Hamburg to protest the upcoming meeting of leaders of the world's major industrialized and emerging economies, known as G-20. 

Police said nearly 10,000 people gathered outside the city hall in Hamburg while canoeists and Greenpeace activists held similar rallies in the nearby Alster River and in the city’s port. 

Organizers said the figure was much higher than the one put by police.  They said a total of 100,000 are taking part in protests that are planned for the days leading to the G-20 summit on Friday and Saturday. 

Security will be tight around the venues of the G-20 summit later this week as nearly 15,000 police officers will be deployed to protect the event.  Some 3,800 officers will also monitor airport and train security. 

The G-20 summit is where U.S. President Donald Trump will make his first visit to Germany.  That could make the situation worse as many have vowed to take to the streets to protest against controversial decisions he has taken over the past several months, including a ban on the entry of nationals from six Muslim-majority nations to the United States.