News In Brief

Top NASA officials have denied charges that shuttle crews have been repeatedly exposed to hazards because of top-level pressures to maintain the launch schedule. This was in response to concerns raised by John W. Young, the head of NASA's astronaut office. And crew cabin debris and some remains of Challenger's astronauts have been recovered from the ocean floor, space center sources say, but NASA said it will not comment until the operation is completed, which could take several days.

Officials said Sunday that families of the astronauts had been notified that a sonar contact was made Friday and that Navy divers made positive identification of the cabin and remains on Saturday, 100 feet below the surface of the Atlantic Ocean.

Mark Weinberg, a spokesman for the presidential commission investigating the shuttle disaster, said he could not comment on the significance of the find to the commission's probe. Data tapes that were in the cabin could shed light on the cause of the explosion, but it was not known the condition of the tapes.

Officials said private boats and planes have been barred from the search area.