Thai Government Holds at Least 200 Leftists, Including Intellectuals
mil junta says it holds at least 200 leftist leaders, including intellectuals, writers and politicians; at least 400 reptdly were seized and released; some 500 students reptdly are still in custody; police rept arresting at least 1,000 curfew violators; junta asks Bangkok movie theaters to stop evening showings to 'guard against possible terror attacks'; number of leftist leaders reptdly return to Bangkok after failing in attempts to flee to Laos; Amer wife of Pansak Vinyaratn says junta let her spend much of day with him in detention cell; author Khamsing Srinawk reptdly flees after police raid his farm, near Korat; Western diplomats fear crackdown is being used, particularly in provincial areas, as excuse for settling grudges (M)