These are the pictures of security during the inauguration that you didn't see

Much like everything President Donald Trump touches, his inauguration didn't come without controversy

The inauguration of Trump — with record-low approval ratings for an incoming president and likely record-low turnout for his ceremony — drew a number of protests. 

And where there's protest, there's often law enforcement. 

In accordance with inauguration protocol and in anticipation of demonstrations, Washington, D.C., was not short of security in its many forms. 

There were violent clashes between protesters and law enforcement Friday: Police let off flash-bangs, fired pepper spray canisters and arrested around 100 people. 

Around 28,000 officials were employed as part of the inauguration's security plan. These included police from departments within and outside D.C., the Coast Guard, the National Guard, Transportation Security Administration personnel and Secret Service, Homeland Security Secretary Jeh Johnson said one week before the ceremony, NPR reports. 

Here are 24 photos of just some of the inauguration's sprawling security plan in action. 

Law enforcement gather amongst BLM protesters
A law enforcement officer looks on
Law enforcement on the streets of Washington, D.C., on Friday
Security personnel interspersed amongst the inauguration crowd
A member of inaugural security looks on at the crowds
A police officer wearing a balaclava walks through the streets of D.C. on Friday.
A member of inaugural security personnel stands in the aisle
Riot police wearing riot gear in Washington, D.C., on Friday
A member of the inaugural security force stands amongst Trump supporters
Security surveys the scene from a distance
A member of inaugural security personnel
Inaugural security personnel walks with a sniffer dog
Military personnel congregate around a vehicle in Washington, D.C.
A member of inaugural security personnel
Riot police respond to a fire started by protesters
A member of the U.S. military surveys the area
High-level security in the streets of Washington, D.C., during Inauguration Day
Law enforcement officers stand with batons in their hands.
Riot police wear headgear in Washington, D.C.
Riot police raise their shields
Smoke from a protester fire billows in the background
Riot police walk through the streets of Washington, D.C., amongst protesters on Inauguration Day.
Smoke from a protester fire rises in the background as riot police respond.
Riot police engage with protesters holding signs