One of the sharpest dividing lines emerging between President Obama and GOP presidential front-runner Mitt Romney is the budget introduced in Congress by Rep. Paul Ryan, R-Wis., with its sharp cuts in domestic spending and lower tax rates.

Both sides see it as a winning issue for the fall campaign. The Obama campaign likes to call it the "Romney-Ryan budget" — and Romney hasn't objected.

On the campaign trail in Wisconsin, Ryan was a constant presence with Romney before that state's April 3 Republican primary, which Romney won.

Since mid-February, the University of Pittsburgh has received more than 50 bomb threats, and while they've all been false alarms, they have succeeded in disrupting campus life. Tighter security measures are now in place, but the threats continue, and students are wondering how they'll be able to make up class work and prepare for final exams.

As North Korea reaches the final stage of preparations for a long-range rocket launch, concern is growing that it is in the early stages of preparing its underground test site for another nuclear explosion.

Pyongyang established the pattern three years ago when it tested a similar rocket and then followed it a month later with a nuclear test.

This time around, there may be a more urgent need to test a nuclear device. The bomb is very likely the result of a significant expansion of North Korea's nuclear weapons program.

Convicted murderer Charles Manson, sentenced to life in prison for his role in the grisly deaths of seven people in 1969, will not be released from prison, California's parole board decided Wednesday. The hearing, which Manson did not attend, may have been the 77-year-old's last chance at freedom. His next bid for a parole hearing isn't likely to be heard until 2027.

The U.S. Geological Survey will soon confirm that the oil and gas industry is creating earthquakes, and new data from the Midwest finds that these man-made quakes are happening more often than originally thought.

Earthquakes happen when faults in the Earth slip and slide against each other. There's continuous stress on innumerable faults on our continent, but seismologists like Bill Ellsworth, from the U.S. Geological Survey, started seeing something odd about 12 years ago.

Florida state attorney Angela Corey, who is acting as a special prosecutor in the high-profile shooting death of teenager Trayvon Martin, has scheduled a 6 p.m. ET news conference to "release new information" regarding the case, her office just announced.