A court hearing connected to the Boston marathonterror bombings.

That is our lead story today.

Hello, everyone, welcome to CNN STUDENT NEWS.

My name is Carl Azuz.

Back in April, two bombs went off near the finish line of the Boston marathon.

Three people were killed, at least 264 others were injured.

The suspects are brothers, Tamerlan and Dzhokhar Tsarnaev.

They are also accused of killing a campus police officer in the days following the bombing.

Tamerlan was killed in the shootout with police.

Dzhokhar was arrested and charged with multiple crimes,

but yesterday's court hearing was for two other people.

Dias Kadyrbayev, in the middle of this photo, and Azamat Tazhayakov to his left.

They are friends of Dzhokhar Tsarnaev.

They have been charged with obstructing justice and conspiracy to obstruct justice.

They weren't involved in the actual bombing.

Authorities say they took items from Tsarnaev's dorm room after the bombing, in order to hidethem from investigators.

Yesterday's hearing was an arraignment,

when defendants are called to court to respond to the charges against them.

It only lasted four minutes.

The two defendants heard the charges against them, entered pleas of not guilty, and were led back out of the court.

Some survivors of a Florida sinkhole are saying a security guard saved lives.

It's part of a resort near Disneyworld, crumbled into the ground Sunday night.

This is how Richard Shanley reacted.

I went door to door, just beating on the doors, trying to get people out, and making sure they were safe.

I went floor to floor, got everybody out, and at the time I got done, I really didn't think about it.

I just got them out and then got out myself.

Everyone in the building made it out safely, no injuries, but that's not always how things work out with sinkholes.

Here's CNN's John Berman.

That's what a sinkhole sounds like,

swallowing the summer bay resort early Monday morning.

The 60-foot wide crater in Claremont, Florida,

just the latest incident in this year's string of sinkholes across the country.

In July, 60-year-old Pamela Knox plummeted into a nearly 20-foot sinkhole, while driving on a busy Toledo, Ohio street.

But some have not been so lucky.

In February, a sinkhole opened up underneath a suburban Tampa home, killing 36-year-old Jeff Bush, who was sleeping in his bedroom.

This is how sinkholes are formed.

A cavity slowly develops in the limestone bedrock.

Over time, it widens, eventually breaking the surface.

Then, the clay and sand above collapse into the hole, swallowing everything in its path.

Repairs can be costly.