New details about the brothers suspected of being behind the Boston Marathon have slowly trickled out today. Investigators are now focusing on a 2011 trip to Russia by the older brother, Tamerlan Tsarnaev, where they believe he became radicalized by extremist groups in the north Caucasus region. Russia had asked the FBI to look into Tamerlan's extremist ties, but the FBI's investigation yielded nothing of note and after interviewing him, kept no tabs on him. "The F.B.I. did not find any terrorism activity, domestic or foreign," the FBI said in a statement.

The FBI said Russia had asked for the investigation "based on information that he was a follower of radical Islam and a strong believer, and that he had changed drastically since 2010 as he prepared to leave the United States for travel to the country's region to join unspecified underground groups."

Russia and the United States have been working closely in the investigation, and Presidents Obama and Putin exchanged a phone call last night, a call initiated by Putin, that stressed how the two countries will be coordinating their investigations despite recent, chilly interactions between the countries.

The younger brother, Dzhokhar Tsarnaev, remains in serious condition, and has yet to give a statement to investigators. Federal prosecutors are currently in the process of drafting charges against him.

On another note entirely, the ambassador to the United States from the Czech Republic has issued a statement asking people on Twitter to stop confusing the Czech Republic with Chechnya. The suspected bombers, who have never lived in Chechnya, but are ethnically Chechen, have confused scores of people by their parents being from a place many have not heard of, and these people believing they are instead hearing "Czech Republic" when Chechnya is said on newscasts. Ignore these people. Avoid these people.

Also, Neil Diamond flew out to Boston on his own dime to sing "Sweet Caroline" with Red Sox fans. Good for Neil.