7 , ▁ 1 9 8 3 . ▁ ▁On ▁that ▁day , ▁the ▁Senate ▁adj ourn ed ▁at ▁ 7 : 0 2   p . m . ▁A ▁crow ded ▁reception , ▁held ▁near ▁the ▁Senate ▁Chamber , ▁broke ▁up ▁two ▁hours ▁later . ▁At ▁ 1 0 : 5 8   p . m ., ▁an ▁explos ion ▁t ore ▁through ▁the ▁second ▁floor ▁of ▁the ▁Capit ol ' s ▁north ▁wing ; ▁the ▁adjacent ▁h alls ▁were ▁virt ually ▁desert ed . ▁ ▁Min utes ▁before ▁the ▁bl ast , ▁a ▁caller ▁claim ing ▁to ▁represent ▁the ▁" Ar med ▁Res istance ▁Unit " ▁war ned ▁the ▁Capit ol ▁switch board ▁that ▁a ▁bomb ▁had ▁been ▁placed ▁near ▁the ▁Chamber ▁in ▁ret ali ation ▁for ▁recent ▁U . S . ▁military ▁invol vement ▁in ▁Gren ada ▁and ▁Leb anon , ▁in ▁which ▁the ▁U . S . ▁had ▁placed ▁Mar ines . ▁ ▁The ▁force ▁of ▁the ▁device , ▁hidden ▁under ▁a ▁ben ch ▁at ▁the ▁eastern ▁end ▁of ▁the ▁cor rid or ▁outside ▁the ▁Chamber , ▁ble w ▁off ▁the ▁door ▁to ▁the ▁office ▁of ▁Democratic ▁Le ader ▁Robert ▁C . ▁By rd . ▁Senator ▁By rd ▁was ▁an ▁active ▁supp orter ▁of ▁invol vement ▁in ▁Gren ada , ▁and ▁had ▁recently ▁made ▁attempts ▁to ▁gar ner ▁support ▁for ▁ret ali ating ▁against ▁recent ▁attacks ▁against ▁US ▁mar ines ▁station ed ▁in ▁Leb anon . ▁His ▁recent ▁actions ▁may ▁have ▁drawn ▁attention ▁from ▁the ▁terror ist ▁group ,