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KNOW IT ALL: Thursday's Top 7 Stories at NBC News

From ISIS's advance in Syria to the release of new documents shedding light on Osama bin Laden, see the stories we're following today.

Good morning. Here are some of the stories we’re following today:

1. ISIS captures ancient city in latest land grab

The terror network said it was in full control of the ancient city of Palmyra on Thursday following a bloody battle with Syrian pro-government forces, a gain rife with strategic as well as historical implications. Aside from being a strategic win for ISIS, Palmyra is also home to a UNESCO world heritage site and famous for its 2,000-year-old ruins. Syrian state TV, meanwhile, acknowledged that pro-government forces had withdrawn from the battlegound. Read more in NEWS.

2. Docs reveal bin Laden’s obsession with conspiracies

Newly released documents — recovered during the 2011 raid in Pakistan that led to al Qaeda leader Osama bin Laden's death — reveal clues into his cloistered life and the terror group's efforts to develop new lines of attack. The documents also include bin Laden's library of English-language books, which indulged his interest in conspiracy theories about the United States. Read more in NEWS.

3. DEA raids ‘pill mills’ in four states

The Drug Enforcement Administration and other authorities raided pharmacies, pain clinics and other facilities in four states Wednesday as part of an aggressive crackdown on prescription pain drug abuse. In Arkansas, for instance, one federal prosecutor described a sting in which undercover officers paid $200 to get prescription drugs from a clinic without ever being examined. Read more in NEWS.

4. Santa Barbara oil spill balloons, closing beach

Crews are continuing to contain crude oil that has fouled the waters off the California coast after a pipeline ruptured Tuesday afternoon. While the flow has been cut off, the estimated size of the spill ballooned to 105,000 gallons Wednesday and has closed a popular local beach ahead of the Memorial Day weekend. Read more in NEWS.

5. Families mourn bikers killed in Waco shootout

Behind the wild story of Sunday's fatal Texas shootout between biker gangs and police outside of a Waco sports bar are the families mourning nine men who died. Some of those relatives told NBC News that not all of the victims were lawless drug dealers and ready for trouble. Security video from inside the Twin Peaks restaurant, meanwhile, showed only one of the dozens of bikers recorded was seen firing a gun from the patio. Read more in NEWS.

6. Sen. Rand Paul ends 'filibuster' of Patriot Act

The Kentucky Republican ended a more than 10-1/2-hour filibuster-like speech on the Senate floor to protest the renewal of the Patriot Act, highlighting his opposition to the NSA's controversial bulk collection of telephone data. While Paul tweeted that he'd launched "a filibuster of the Patriot Act renewal," his speech was not a true filibuster because it did not delay consideration of any bill. Read more in NEWS.

7. D.C. gyrocopter pilot indicted by grand jury

Douglas Hughes, the Florida letter carrier who violated national airspace by landing his open-cockpit aircraft on Capitol Hill last month, could face 9-1/2 years in prison after he was indicted Wednesday by a federal grand jury. Hughes has said the airborne breach was to protest the influence of big money in politics by delivering letters to each voting member of Congress. Read more in NEWS.

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