Bipartisan U.S. Senate negotiations on how or if to respond to the latest wave of mass shootings are focused on a range of options, including improving school safety and “red flag” laws to allow police to seize guns from people deemed dangerous.

The talks will continue into early this week, when Congress returns from a Memorial Day break, and follow a prime-time speech last week in which Democratic President Joe Biden implored lawmakers to act.

Previous mass shootings like the ones that claimed 19 young children and two educators at a Texas school, 10 Black shoppers at a New York state grocery store and a pair of weekend shootings in Philadelphia and Chattanooga, Tennessee, have led to similar talks but no action in the deeply divided Congress.

Democratic U.S. Senator Chris Murphy, who is leading the talks with Republican counterpart John Cornyn, said options on the table included investments in mental health and school safety.

“Do some significant mental health investment, some school safety money and some modest but impactful changes in gun laws. That’s the kind of package we’re putting together right now. That’s the kind of package I think can pass the Senate,” Murphy said in an interview on CNN’s “State of the Union” Sunday.

Democrats control razor-thin majorities in Congress, but Senate rules mean they need at least 10 Republicans to pass major legislation. That is a tall order with less than six months before November midterm elections when Republicans aim to retake the majority.

U.S. Senator Pat Toomey, a Republican member of the negotiating group, said some expansion of background checks is on the table, along with possible “red flag” laws that allow states to maintain adequate due process.

“I think there is a place to land that is consistent with the Second Amendment,” Toomey said, speaking on CBS’s “Face the Nation” program. “It hasn’t been finally resolved but something in the space of expanding background checks I think is very – well, certainly is on the table and I hope will be part of a final package.”

The Second Amendment of the U.S. Constitution protects the right to keep and bear arms, and Republicans defend a broad reading of that right, opposing most new limits on gun ownership.

While the White House and Congress struggle to agree on any response to the wave of shootings, the U.S. Supreme Court this month is expected to rule on a New York case that could bring a sweeping expansion of gun rights.

“Red flag” laws allowing police to seize weapons from people with some mental illnesses have been implemented in 19 U.S. states. Gun rights advocates criticize such measures, saying they violate the Second Amendment and deny individuals the right to argue their cases with due process in court.

Murphy, of Connecticut, where a gunman killed 26 children and educators at the Sandy Hook Elementary School in 2012, said parents in his state are worried.

“There’s just a deep, deep fear for our children right now. And also, a fear that government is so fundamentally broken that it can’t put politics aside to guarantee the one thing that matters most to adults in this country – the physical safety of their children,” he told CNN.