Motivated by applications in DNA-based storage and communication systems, we study deletion and insertion errors simultaneously in a burst. In particular, we study a type of error named t-deletion-1-insertion-burst ((t, 1)-burst for short) proposed by Schoeny et. al, which deletes t consecutive symbols and inserts an arbitrary symbol at the same coordinate. We provide a spherepacking upper bound on the size of binary codes that can correct (t, 1)-burst errors, showing that the redundancy of such codes is at least log n+t−1. An explicit construction of a binary (t, 1)-burst correcting code with redundancy log n+(t−2) log log n+O(1) is given. In particular, we construct a binary (3, 1)-burst correcting code with redundancy at most log n + 9, which is optimal up to a constant.